Platinum- mineral, natural Pt from the platinum group of the class of native elements, usually contains Pd, Ir, Fe, Ni. Pure platinum is very rare, most of the samples are represented by a ferruginous variety (polyxene), and often intermetallic compounds: isoferroplatinum (Pt,Fe) 3 Fe and tetraferroplatinum (Pt,Fe)Fe. Platinum, represented by polyxene, is the most common mineral of the platinum subgroup in the earth's crust.
See also:
STRUCTURE
The crystal lattice of platinum belongs to the cubic system. The cyclohexene molecule has the shape of a regular hexagon. In the reaction system under consideration, the atomic structure of the catalyst and the reacting molecules have one common property—third-order symmetry elements. In a platinum crystal, this arrangement of atoms is inherent only in the octahedral face. The nodes contain platinum atoms. a = 0.392 nm, Z = 4, space group Fm3m PROPERTIES
The color of polyxene is silver-white to steel-black. The dash is metallic steel grey. The luster is typical metallic. Reflectivity in polished sections is high - 65-70.
Hardness 4-4.5, for iridium-rich varieties - up to 6-7. Has malleability. The fracture is hooked. Cleavage is usually absent. Oud. weight-15-19. A connection between a reduced specific gravity and the presence of voids occupied by natural gases, as well as inclusions of foreign minerals, was noted. It is magnetic, paramagnetic. Conducts electricity well. Platinum is one of the most inert metals. It is insoluble in acids and alkalis, with the exception of aqua regia. Platinum also directly reacts with bromine, dissolving in it.
When heated, platinum becomes more reactive. It reacts with peroxides, and upon contact with atmospheric oxygen, with alkalis. A thin platinum wire burns in fluorine with the release of a large amount of heat. Reactions with other non-metals (chlorine, sulfur, phosphorus) are less active. With stronger heating, platinum reacts with carbon and silicon, forming solid solutions, similarly to the metals of the iron group.
RESERVES AND PRODUCTION
Platinum is one of the rarest metals: its average content in the earth's crust (clarke) is 5 10 -7% by weight. Even the so-called native platinum is an alloy containing from 75 to 92 percent platinum, up to 20 percent iron, as well as iridium, palladium, rhodium, osmium, less often copper and nickel.
The explored world reserves of platinum group metals are about 80,000 tons and are distributed mainly between South Africa (87.5%), Russia (8.3%) and the USA (2.5%).
In Russia, the main deposits of platinum group metals are: Oktyabrskoye, Talnakhskoye and Norilsk-1 sulfide-copper-nickel deposits in the Krasnoyarsk Territory in the Norilsk region (more than 99% of the explored and more than 94% of the estimated Russian reserves), Fedorova Tundra (Bolshoy Ikhtegipakhk area) sulfide- copper-nickel in the Murmansk region, as well as placer Kondyor in the Khabarovsk Territory, Levtyrinyvayam in the Kamchatka Territory, the Lobva and Vyysko-Isovskoe rivers in the Sverdlovsk Region. The largest platinum nugget found in Russia is the "Ural giant" weighing 7860.5 g, discovered in 1904. at the Isovsky mine.
Native platinum is mined at mines, loose deposits of platinum are less rich, which are explored mainly by the method of schlich sampling.
The production of platinum in powder form began in 1805 by the English scientist W. H. Wollaston from South American ore.
Today, platinum is obtained from a concentrate of platinum metals. The concentrate is dissolved in aqua regia, after which ethanol and sugar syrup are added to remove excess HNO 3 . In this case, iridium and palladium are reduced to Ir 3+ and Pd 2+ . Ammonium hexachloroplatinate(IV) (NH 4) 2 PtCl 6 is isolated by subsequent addition of ammonium chloride. The dried precipitate is calcined at 800-1000 °C
The sponge platinum thus obtained is subjected to further purification by redissolving in aqua regia, precipitation of (NH 4 ) 2 PtCl 6 and calcining the residue. The purified spongy platinum is then melted down into ingots. When recovering solutions of platinum salts by a chemical or electrochemical method, finely dispersed platinum - platinum black is obtained.
ORIGIN
The platinum group minerals are mostly found in typical igneous deposits genetically related to ultramafic igneous rocks. These minerals in ore bodies stand out among the latter (after silicates and oxides) at the moments corresponding to the hydrothermal stage of the magmatic process. Platinum minerals poor in palladium (polyxene, iridescent platinum, etc.) are found in deposits among dunites, olivine feldspar-free rocks rich in magnesia and poor in silica. At the same time, they are paragenetically closely related to chrome spinels. Palladium to nickel-palladium platinum is predominantly distributed in the main igneous rocks (norites, gabbro-norites) and is usually associated with sulfides: pyrrhotite, chalcopyrite and pentlandite.
Under exogenous conditions, in the process of destruction of primary deposits and rocks, platinum-bearing placers are formed. Most minerals of the platinum subgroup are chemically stable under these conditions. Platinum in placers occurs in the form of nuggets, flakes, plates, cakes, concretions, as well as skeletal forms and spongy secretions ranging in size from 0.05 to 5 mm, sometimes up to 12 mm. Flattened and lamellar grains of platinum indicate a significant distance from primary sources and redeposition. The range of platinum transfer in placers usually does not exceed 8 km, in oblique placers it is longer. The palladium and cuprous varieties of platinum in the hypergenesis zone can be "ennobled", losing Pd, Cu, Ni. The content of Cu and Ni, according to A.G. Betekhtin, in platinum from placers can be reduced by more than 2 times compared to platinum from the primary source. In the placers of many regions of the world, newly formed chemically pure platinum and palladium platinum are described in the form of sintered forms of a radial-radiant structure.
APPLICATION
Platinum compounds (mainly aminoplatinates) are used as cytostatics in the treatment of various forms of cancer. Cisplatin (cis-dichlorodiammineplatinum(II)) was the first to be introduced into clinical practice, but more effective carboxylate complexes of diammineplatinum - carboplatin and oxaliplatin - are currently used.
Platinum and its alloys are widely used for jewelry production.
The world's first platinum coins were issued and were in circulation in the Russian Empire from 1828 to 1845. Minting began with three-rouble coins. In 1829, “platinum duplons” (six-ruble notes) were established, and in 1830, “quadruples” (twelve-ruble notes). The following denominations of coins were minted: denominations of 3, 6 and 12 rubles. Three-ruble coins were minted 1,371,691 pieces, six-ruble notes - 14,847 pieces. and twelve rubles - 3474 pcs.
Platinum was used in the manufacture of insignia for outstanding services: the image of V. I. Lenin was made from platinum on the Soviet Order of Lenin; the Soviet order "Victory", the order of Suvorov of the 1st degree and the order of Ushakov of the 1st degree were made from it.
- Since the first quarter of the 19th century, it has been used in Russia as an alloying additive for the production of high-strength steels.
- Platinum is used as a catalyst (most often in an alloy with rhodium, and also in the form of platinum black - a fine powder of platinum obtained by reducing its compounds).
- Platinum is used to make vessels and stirrers used in the melting of optical glasses.
- For the manufacture of chemically and strong heat-resistant laboratory glassware (crucibles, spoons, etc.).
- For the manufacture of permanent magnets with high coercive force and residual magnetization (an alloy of three parts of platinum and one part of cobalt PlK-78).
- Special mirrors for laser technology.
- For the manufacture of durable and stable electrical contacts in the form of alloys with iridium, for example, contacts of electromagnetic relays (alloys PLI-10, PLI-20, PLI-30).
- Galvanic coatings.
- Distillation retorts for the production of hydrofluoric acid, obtaining perchloric acid.
- Electrodes for the production of perchlorates, perborates, percarbonates, peroxysulfuric acid (in fact, the use of platinum determines the entire world production of hydrogen peroxide: electrolysis of sulfuric acid - peroxysulfuric acid - hydrolysis - distillation of hydrogen peroxide).
- Insoluble anodes in electroplating.
- Heating elements of resistance furnaces.
- Production of resistance thermometers.
- Coatings for elements of microwave technology (waveguides, attenuators, resonator elements).
Platinum - Pt
CLASSIFICATION
| Strunz (8th Edition) | 1/A.14-70 |
| Nickel-Strunz (10th edition) | 1.AF.10 |
| Dana (7th edition) | 1.2.1.1 |
| Dana (8th edition) | 1.2.1.1 | Hey's CIM Ref | 1.82 |
PHYSICAL PROPERTIES
OPTICAL PROPERTIES
CRYSTALLOGRAPHIC PROPERTIES
| dot group | m3m (4/m 3 2/m) - isometric hexaoctahedral |
| space group | Fm3m |
| Syngony | cubic |
| Cell Options | a = 3.9231Å |
| Twinning | total by (111) |
Jewelers call platinum the queen of precious metals. But it was not always so. Until the 18th century, it was not mined on an industrial scale, and even called “bad silver”. Let's figure out what platinum is and what is its value. We learn a lot of interesting facts about how it looks in its original form,.
If you are a happy owner of a platinum jewelry or just want to become one, find out.
It is a silver colored precious metal. Outwardly, it resembles silver, but has completely different physical and chemical properties.
Platinum deposits are rarely found in nature. Their development is extremely labor intensive. For these reasons, the value of the metal on the market is even higher than that of gold.
Expert opinion
Vsevolod Kozlovsky
Platinum (as denoted in chemistry, Pt, platinum) is one of the elements of the periodic table. It is a dense, hard, but very plastic material.
Brief history of appearance
As a jewelry metal, the ancient Egyptians, Incas and Chibcha tribes used it. Platinum came to the European continent along with Spanish sailors from South America. The precious metal was not appreciated at that time. Even the word platina in Spanish sounds like "dirty silver". Since it has a high density, it is refractory, it was considered unfit for consumption. Often even thrown away.
Fraudsters were the first to use Pt in jewelry. It was added to gold alloys, increasing the weight of the item without reducing the cost. Production took such a scale that the import of platinum into Europe was banned.
Only in the middle of the 18th century was metal isolated as a separate chemical element. Properties were studied - operational, physical. At the turn of the 19th century, scientists found out that platinum is not just a noble metal, but also serves as the “mother” for a whole family of platinoids:
- palladium;
- rhodium;
- osmium;
- iridium.
What does platinum look like in nature?
It does not occur in its pure form in nature. Forms isomorphic mixtures with iron, copper, silver, nickel, platinum group metals. Platinum-containing ore has small grains, inclusions of the precious metal.
Native metal is mined nuggets containing from 75 to 92% Pt. They are rarely found. Ferrous platinum (polyxene) is mainly mined, which contains 20-50% iron.
The process of education in nature
Platinum ores are in a dispersed state. They are of igneous origin, released through the crystallization of basic and ultrabasic magmas. At a temperature of 1300-1500 degrees, sulfides, platinum, chloride, osmium, and iridium are separated from the silicate melt.
The surface of primary deposits is destroyed over time. The placers formed as a result of this are convenient for industrial development.
Structure, chemical and physical properties
Expert opinion
Vsevolod Kozlovsky
6 years in jewelry business. Knows everything about samples and can identify a fake in 12 seconds
The structural structure of the crystal lattice is a cube with elements of symmetry of the third order. , low thermal conductivity, high density (21.45 gr. per dm2). Melting point - 1769 degrees, boiling point - 3800.
Hard material is difficult to process. It is so durable that it is possible to make jewelry from pure platinum without the addition of impurities.
Other physical and chemical properties:
- plasticity when heated (you can make the thinnest foil or wire);
- resistance to corrosion, oxidation;
- lack of interaction with acids and alkalis;
- low resistivity (serves as a good conductor);
- catalyst for many chemical reactions.
Also look in the video and other properties of platinum:
How are platinum veins found?
The main place of extraction is copper, nickel deposits (primary and alluvial). Of these, platinum is mined along with other metals. Platinum nuggets are found in ultramafic igneous rocks. Natural mineral ores with a high element content are rare.
Satellites of platinum
In platinum deposits, platinum group metals accompany.
In addition, in various rocks, platinum is found with the following associated minerals:
- Basic and ultrabasic magmas - serpentine, chromite, magnetite, chrysotile-asbestos, olivine, orthorhombic pyroxenes.
- Placers - chromite, corundum, magnetite, gold, diamonds.
- Diabase - chalcopyrite.
Where is platinum found in nature?
It is the rarest element in the Earth's crust.
It occurs as nuggets, alloys with nickel, copper, platinum group metals.
Deposits where platinum is found are associated with basic and ultrabasic igneous rocks.
Types of deposits
The deposits of the Ural type are associated with ultrabasic rocks (Urals, South Africa, Columbia, Alaska). Platinum, osmium, iridium are contained in the main rocks with a high content of iron, nickel, and copper sulfates.
The second type of deposits is copper-nickel sulfide. In the composition of ores, platinum group metals are combined with bismuth, sulfur, antimony, and arsenic. They contain, in addition, gold, silver, palladium.
Top countries by production
The leading countries in the world market are:
- Republic of South Africa.
- Russia.
- Zimbabwe.
- Canada.
World reserves of platinum
80% of the deposits of platinum group metals available for development are located in South Africa (the Bushveld complex in the north of the country).
The second in terms of reserves is the GreatDyke field (Zimbabwe).
3rd and 4th place in the Russian Federation and North America (USA, Canada). Canadian platinum ores are concentrated in the provinces of Ontario and Manitoba. In the US, the bulk of production comes from two major mines in Montana.
Colombian alluvial deposits are saturated with platinum group metals. They are concentrated in the west of the Cordillera, in the river valleys of the Atrato, San Juan.
Mining methods
The production process consists of three stages:
- Ore mining.
- Enrichment.
- Obtaining a precious metal of high purity.
Extracting platinum from the earth's interior is a laborious and expensive task. More than 10 tons of ore are processed to extract 1 ounce (31.1 gr.) of precious metal.
There are two ways to get it:
- open;
- underground.
The first option is suitable for alluvial deposits formed as a result of the destruction of the primary rock. It involves the use of quarry equipment, dredges, hydromechanical means.
Primary deposits, buried placers are developed by an underground method. Mines are being dug, holes are drilled in them by hand, and explosives are planted. Pieces of rock that have broken off are brought to the surface by miners for further processing. Today, this option of metal mining is significantly mechanized, but it cannot do without manual labor.
Applications
The industries where platinum is used are varied.
List of applications:
- oil and gas industry (obtaining high-octane gasoline and technical hydrogen from oil fractions);
- automotive industry (manufacturing of catalysts for afterburning exhaust gases);
- electrical engineering (elements of high-temperature furnaces, mirrors for lasers, magnets);
- ammonia synthesis;
- chemical, glass industry (equipment with high resistance to chemical and thermal influences, electrodes, reaction catalysts);
- medical instruments;
- jewelry making.
The richest platinum deposits
The total world reserves in known deposits are about 66 thousand tons. Most of them are located in South Africa (63 thousand tons). Russian deposits are rich in 1.1 thousand tons, American - 0.9 thousand tons, Canadian - 0.3 thousand tons, other countries - 0.7 thousand tons.
In the world
The largest deposits of platinum-bearing ores are located in South Africa. These are the ultramafic rocks of the Paleozoic era in the Bushwell.
Other major world deposits:
- Sudbury (Canada);
- Nevada, California, Wyoming, Alaska (USA);
- Quibdo, Andagoda, Opogodo, Tamana, Kondoto-Iro (Colombia);
- Norway, New Zealand.
In Russia
For the first time on the territory of the Russian Federation, deposits were discovered in the 20s of the XIX century in the Urals Verkh-Isetsky district.
The main deposits of platinum:
- October;
- Talnakhskoye;
- Nizhny Tagil;
- sulfide-copper-nickel in Norilsk, Krasnodar Territory, Fedorov Tundra, Zarechenskoe in the Murmansk Region;
- alluvial deposits in the Khabarovsk Territory (Konder), on Kamchatka (Levtyrinyvayam), on the Lobva River, Vyysko-Isovskoye.
Advantages and disadvantages
The advantages of platinum are due to its physical and chemical properties. Among them, hardness, low thermal conductivity, high density, refractoriness. The metal does not deform when heated, it is resistant to corrosion. It is almost impossible to bend, deform.
Jewelry made of platinum is hypoallergenic, wear-resistant, durable.
The durability and strength of the precious metal is evidenced by the fact that at the end of the 18th century standards of the kilogram and meter were made from it.
Against the background of all these advantages, there is only one drawback. This is the price. The cost of platinum products is much higher than gold ones.
Kinds
Native platinum is classified according to the content of other components in the ore. There is palladium platinum (40% palladium), nickel platinum (3% nickel), rhodium platinum (5% rhodium), cuproplatinum (10-15% copper), ferrous platinum (25% nickel and iron each).
From enriched pure platinum, dimensional, stamped ingots of 999 samples are produced. Due to the high cost, Pt jewelry is usually small and monolithic.
Alloys and samples
Platinum alloys, like the pure element, have a grayish-white hue with a characteristic sheen.
The list indicates what the ligature consists of. For the alloy take one or more of the following components:
- copper;
- rhodium;
- palladium;
- gold;
- cobalt;
- iridium.
Products made of precious metals, including platinum, are subject to mandatory approbation. Affixing the state hallmark confirms the conformity of the alloy to a particular sample.
According to the metric system adopted in Russia for platinum, 850, 900, 950, 999 samples are approved. Stamp - a rectangle with beveled edges, which depicts the profile of a woman in a kokoshnik and the digital designation of the sample.
Sample matching table
The metric system shows how many units of pure precious metal are in 1000 units of the alloy. Carat assay is based on pure metal as 24 units. The formula for converting a metric sample into a carat: sample × 24/100.
| Metric | carat |
| 850 | 20 |
| 900 | 22 |
| 950 | 23 |
| 999 | 24 |
Where can you buy or sell
Demand in the platinum sales market still exceeds its supply. This is due to the complex extraction of it from the bowels. Ingots, coins made of high purity platinum can be bought in banks. They can also be bought back there (as a rule, with a certificate and receipt). Platinum jewelry, which is made by famous jewelry houses, cannot be found in an ordinary store.
You can sell platinum jewelry or scrap at a pawnshop or buying. The price there will not be the best. Of the benefits - the money will be issued immediately. Thrift stores can sell items at the best price, but it may take a day. Money will be given to the seller only after the sale of the goods.
A favorable price can be obtained by selling at auctions, including on the Internet. But an inexperienced seller in pursuit of profit can run into scammers.
I advise you to find collectors. They will evaluate the value of the product not only in grams, but also taking into account its artistic, historical, jewelry value. In this case, you can sell the jewelry at a price as close as possible to the market price.
How much does 1 gram cost today
Prices per ounce of the precious metal are set twice a day on the London Stock Exchange. The figure is taken as a basis by the central banks of world countries, including the Central Bank of the Russian Federation. Below is a live chart and .
Platinum | Rub | 1 Gram
Platinum | USD | 1 Gram
Scrap price
All products accepted by the pawnshop are valued as scrap. The cost of platinum scrap, of course, is lower than the market value - by about 15-20%. Some pawnshops price jewelry by category. For high-quality things, a large amount per gram is issued.
How to distinguish a fake
The silvery luster of platinum resembles silver. Let's figure out how not to fall for scammers and distinguish a real platinum jewelry from a fake.
The element does not react to alkalis and acids. There is a simple homemade rotten egg test that contains hydrogen sulfide. By what color the product will become, you can determine what is in front of you. Silver will turn black, platinum will not.
The old-fashioned biting method will help determine how soft the metal is in front of you. Platinum alloys are very hard, they do not leave traces of deformation. Of course, not every buyer will risk their teeth. And the sellers are not happy with this definition of authenticity.
A distinctive characteristic of platinum is its low thermal conductivity. When heated, heat spreads more slowly than other metals.
I advise you to pay attention to the stigma. Images, numbers, contours of the print must be clear, without deformation. If you have doubts about the authenticity of a precious metal, you can contact a specialist - a jeweler or an appraiser at a pawnshop.
It is always better to buy jewelry in large specialized stores that have documents and value their reputation.
Resist the urge to buy platinum on the cheap. . It cannot be worth a little more than silver or like gold. Due to the high cost of raw materials, platinum jewelry is made small in size. They are molded, not blown.
Jewelry should be removed before doing homework, especially if there is going to be contact with aggressive cleaning agents. The surface of the decoration may fade. Store platinum separately from other precious metals.
Minor dirt is removed by soaking the jewelry in soapy water. We advise you to entrust things encrusted with precious stones to a professional. This service is provided in jewelry workshops.
Platinum is perhaps the most noble of metals. Items made of pure platinum are as rare as they are expensive. This is one of the hypostases of Neptune; it is associated with mystery, contemplation, a high degree of initiation, religious mysticism, spirituality, insight.
It activates the natural talent of the medium, contributes to the acquisition of revelations and prophetic visions, enhances empathy - therefore, the wearing of this metal is especially recommended for clergymen, as well as doctors, in particular those who work with the human psyche.
In general, platinum favors those who devote their lives to high service, sacrificing vain worldly desires and ambitions to it. It helps those who have chosen the path of self-improvement through prayer and renunciation of their own ego to go through the path of spiritual transformation.
Platinum has practically no negative qualities; but she categorically does not tolerate a certain category of people and will only bring them trouble - these are, first of all, unceremonious, rude, mentally hardened people who allow themselves to invade someone else's life. Platinum punishes especially severely for theft, even, as they say, “little things” - according to some sources, it even punishes quite physically, provoking the carrier of the disease and bone fractures.
With all this, the favorable energy of platinum is manifested in wisdom, tolerance and forgiveness; this is the personification of a generous and merciful higher power, repaying according to merit, but mitigating punishment.
Platinum has a positive effect on people of the water or water-air element, especially those who were born under the sign of Pisces. The platinum chain elevates the spirit and helps to find the way to Paradise, so it is best suited for those who are ministers of the Church; such decoration will also benefit people of artistic professions.
A platinum ring contributes to the achievement of truly great goals, not stopping there and not following the path of least resistance. Such a ring, so that it "works", should only be donated, and not bought on its own.
Platinum earrings make a person actually forget about his gender, setting him on the same wavelength with the universe and giving a sense of belonging to the Cosmos.
Platinum is a popular expensive metal that is widely used in jewelry. But, the value of platinum lies in the powerful energy of this metal and its impact on the human body. What is the effect of platinum jewelry on health?
Often, platinum jewelry is advised to be worn by people of mature age, women mostly prefer earrings and rings, chains with pendants.
It is believed that platinum has the power of Neptune in itself, since its capabilities are so strong that they can affect not only the life and health of a particular person, but also the fate of entire generations. Neptune unites all the smallest energy shells of a person into a single whole and directs the received energy to the internal organs. The influence of Neptune on the energy level resembles the influence of sea water.
Platinum is considered to be quite strong and at the same time good metals. It has an impact on the human body, connecting with the energy of the Cosmos. This metal helps restore peace of mind, brings success in intellectual work, and also increases the power of intuition.
The outstanding ability of platinum is the transformation of the work of all organs from an extreme state to a calm one. Since it normalizes their work and prevents the exacerbation of various inflammatory processes. When such diseases are already present, platinum softens their course. Such a precious metal brings sound and healthy sleep to those who wear it.
The specificity of platinum is that its influence is more aimed not at the mind, but at the subconscious part, so to speak, at the astral body.
Platinum works quite well on the activity of the urinary organs, it also affects the excretion of chemicals and toxins from the body.
However, despite the fact that this metal copes with great mental stress and somatic ailments that manifest as a result of stress, platinum is forbidden to be worn by people with an unstable psyche, in particular with schizophrenia.
To obtain a wellness result, it is advised to wear a platinum ring, paying attention to the following aspects:
- men put on the middle finger of the left hand, and women - on the middle finger of the right. In addition, women are advised to wear after the full moon.
- it is necessary to put on a platinum ring for 6 days, alternating with three day breaks. Wearing time is not limited, but it is advised to periodically remove the ring and clean it, thus allowing you to rest for a couple of weeks.
It also matters on which finger the platinum is worn:
- on the nameless - contributes to the improvement of extrasensory abilities, and normalizes the work of the cardiovascular system;
- on the index - affects spiritual development and insight;
- on the middle finger - increases the overall immunity of the body, affects the extension of life;
- It is forbidden to wear platinum on the little fingers and thumbs, even for a short time. This can cause a sharp drop in energy and sudden illnesses.
Platinum is a heavy, refractory precious metal of silver-white color, density 21.45 g / cm3, melting point 1773.5 ° C, boiling point - 4410 ° C. Harder than gold and silver. Indicated by the symbol Pt. The name comes from the Spanish word plata - "silver"; platina is a diminutive form, literally "little silver" or "silver".
Platinum can be easily processed by pressure (forging, rolling, drawing). It is characterized by high chemical resistance: it dissolves only in hot aqua regia, potassium cyanide and molten alkalis. Separately, none of the acids affects this metal. Platinum does not oxidize in air, even with strong incandescence, and when cooled, it retains its natural color.
Platinum is one of the rarest elements, its average concentration in the earth's crust is 5 10 -7% by weight. It occurs in native form, in the form of alloys and compounds. Until the 18th century, platinum was unknown in Europe. In 1748, the Spanish mathematician and navigator A. de Ulloa was the first to bring samples of native platinum found in Peru to the European continent. The Italian chemist Gilius Scaliger discovered in 1735 that platinum is indecomposable and thus proved that it is an independent chemical element. For the first time, platinum was obtained in pure form from ores by the English chemist W. Wollaston in 1803.
PROPERTIES OF PLATINUM
Physical properties of platinum. It crystallizes into face-centered cubic lattices. When salt solutions are exposed to reducing agents, the metal can be obtained in the form of “niello” with high dispersion.
Platinum is able to absorb certain gases on the surface, especially hydrogen and oxygen. The tendency to absorption increases significantly for a metal that is in a finely dispersed and colloidal state. Platinum black strongly absorbs oxygen: 100 volumes of oxygen per volume of platinum black.
Platinum characteristic:
- color grayish-white, shiny;
is the atomic radius, nm 0.138;
— crystal lattice parameters at 20 °C, nm a = 0.392;
— density at 20 °С, kg/dm3 21.45;
— melting point, °С 1773.5;
— boiling point, °С 4410;
—specific heat capacity, J/(mol/K) 25.9;
— thermal conductivity at 25 °C, W/(m K) 74.1;
— electrical resistivity at 0 °С, μΩ cm 9.85;
- Brinell hardness, MPa 390 - 420;
— modulus of elasticity, GPa 173.
Chemical properties of platinum. Fully reacts only with hot aqua regia:
3Pt + 4HNO3 + 18HCl = 3H2 + 4NO + 8H2O.
Its dissolution in sulfuric acid heated to a certain temperature and in bromine proceeds extremely slowly.
When heated, it reacts with alkalis and sodium peroxide, halogens (especially in the presence of alkali metal halides):
Pt + 2Cl2 + 2NaCl = Na2.
When heated, platinum reacts with oxygen to form volatile oxides. The following platinum oxides have been isolated: black PtO, brown PtO2, reddish brown PtO3, Pt2O3, and Pt3O4.
Platinum metal does not have a toxic effect on the human body, however, the impurities contained in platinum black (primarily tellurium) are poisonous and, if they enter the gastrointestinal tract, they occur: necrosis of the gastrointestinal mucosa, granular degeneration of hepatocytes, swelling of the epithelium of the convoluted tubules kidneys, as well as “general intoxication”.
Healing properties of platinum. Metal nanoparticles are able to freely penetrate directly into the cells of the body and have a positive effect on vital processes. The main function of platinum is considered to be the destruction of free radicals, thus slowing down the process of premature aging. Platinum is also found in some drugs used to treat cancer.
The magical properties of platinum. According to its magical properties, this metal is light and pure, does not carry any evil in itself, does not store, unlike gold, a negative memory. Platinum has a clear connection with the cosmos. The mission of platinum is to bring people goodness and wisdom, enlightenment of the soul and enlightenment of the mind. A product made of platinum should be made a talisman for medical staff, as well as people of those professions where sensitivity to others is central. Jewelery made of rare metal can increase a hundredfold everything positive that is in a person, and neutralize the negative. They will sharpen intuition, show their owner the right path and protect against negative external influences that destroy his energy shell.
HISTORY OF PLATINUM IN RUSSIA
In Russia, platinum was first found in the Urals, in the Verkh-Isetsky district, in 1819. When washing gold-bearing rocks, white shiny grains were noticed in gold, which did not dissolve even in the strongest acids.
In 1823 V.V. Lyubarsky, Berg-assayer of the laboratory of the Petersburg Mining Corps, examined these grains and established that the mysterious "Siberian metal belongs to a special kind of raw platinum containing a significant amount of iridium and osmium."
In 1824, pure platinum placers were discovered in the Urals. These deposits were exceptionally rich and immediately brought Russia to the first place in the world in the extraction of platinum.
In 1826, an outstanding engineer of his time, P.G. Sobolevsky together with V.V. Lyubarsky developed a simple and reliable method for obtaining malleable platinum.
On March 21, 1827, in the conference hall of the St. Petersburg Mining Cadet Corps, at a crowded solemn meeting of the Scientific Committee for the Mining and Salt Part, the first products made from Russian platinum made by the new method were shown - wire, bowls, crucibles, medals, an ingot weighing 6 pounds.
Since 1828, platinum coins of 3, 6, and 12 ruble denominations began to be issued in Russia.
In 1843, 3500 kg of platinum was already mined. This affected the price, platinum became cheaper.
In 1845, by special decree, due to the fear of counterfeiting and importation of platinum coins from abroad, all platinum coins were withdrawn from circulation within six months.
In 1867, a royal decree abolished the state monopoly on platinum and permitted its duty-free export abroad. Taking advantage of the favorable market conditions, England bought up all the reserves of this metal - more than 16 tons.
Before the First World War, platinum production in Russia amounted to 90...95% of the world production.
In May 1918, the Institute for the Study of Platinum was established, which later merged into the Institute of General and Inorganic Chemistry of the USSR Academy of Sciences, now named after Academician N.S. Kurnakov.
Platinum mining
Pure platinum is very rare in nature. The main form of its presence in the ore is its own minerals, of which about 90 are known. The polyxene mineral contains 80 ... 88% Pt and 9 ... 10% Fe; cuproplatinum – 65…73% Pt, 12…17% Fe and 7.7…14% Cu; Nickel platinum also includes iron, copper and nickel. Known natural alloys of platinum only with palladium or only with iridium. There are also a few minerals - compounds of platinum with sulfur, arsenic, antimony.
Industrial use is technically possible and economically feasible if the ores contain platinum metals:
- in primary deposits proper from 2 - 5 g / t to units of kg / t;
- in indigenous complex - from tenths to hundreds (occasionally thousands) g / t;
— in alluvial deposits — from tens of mg/m3 to hundreds of g/m3.
Significant accumulations of ore in the form of deposits are very rare.
Ore is mined by open and underground methods. The majority of alluvial deposits and part of primary deposits are developed by the open method. The underground mining method is the main one in the development of primary deposits; sometimes it is used to mine rich buried placers.
After wet enrichment of the ore, a "raw" concentrate is obtained - a concentrate with 70 - 90% of metal minerals. This concentrate is sent for refining. Enrichment of complex sulfide ores is carried out by flotation followed by multi-operational pyrometallurgical and electrochemical processing.
The main part of platinum deposits (more than 90%) lies in the bowels of five countries. These include South Africa, USA, Russia, Zimbabwe, China.
In 2008, 200 tons of platinum were mined in the world. The leaders in production were: South Africa - 153.0 tons, Russia - 25.0 tons, Canada - 7.2 tons, Zimbabwe - 5.6 tons, USA - 3.7 tons, Colombia - 1.7 tons.
The leader in platinum mining in Russia is MMC Norilsk Nickel. The largest platinum nuggets displayed at the exhibition of the USSR Diamond Fund weigh 5918.4 and 7860.5 grams.
The explored world reserves of platinum group metals are about 80,000 tons and are distributed mainly between South Africa (87.5%), Russia (8.3%) and the USA (2.5%).
Platinum production
From the mines, raw platinum goes to the refinery. Here it is subjected to prolonged heating in porcelain cauldrons with aqua regia. As a result, almost all platinum and palladium, partly rhodium, iridium, ruthenium and the bulk of base metals go into solution.
Platinum in solution is in the form of two complexes:
H2 - most and
(NO)2.
By adding HCl to the solution, the (NO)2 complex is destroyed so that all platinum is converted into the H2 complex.
Further, the iridium, palladium, rhodium present in the solution is converted into compounds that are not precipitated by ammonium chloride, and then the solution is “adjusted” by heating it with acids (sulfuric or oxalic) or (according to the Chernyaev method) with a sugar solution.
Now you can enter ammonia and precipitate platinum in the form of ammonium chloroplatinate. A solution of ammonium chloride is administered in the cold. In this case, the main part of platinum in the form of small bright yellow crystals (NH4)2 precipitates. The precipitate is further cleaned with a solution of ammonia and dried. The dry residue is placed in an oven. After several hours of calcination at 800–1000°C, spongy platinum is obtained in the form of a sintered steel-gray powder.
The resulting sponge is crushed and washed again with hydrochloric acid and water. Then it is melted in an oxy-hydrogen flame or in a high-frequency furnace. This is how platinum bars are obtained.
When platinum is mined from sulfide copper-nickel ores, in which its content does not exceed a few grams per ton of ore, platinum and its analogues are sourced from the sludge of copper and nickel electrolysis shops. Sludge is enriched by roasting, secondary electrolysis, and other methods. In the resulting concentrates, the content of platinum and its eternal companions - platinoids - reaches 60%, and they can be extracted from concentrates in the same way as from raw platinum.
APPLICATION OF PLATINUM
Over the past 20...25 years, the demand for platinum has increased several times and continues to grow. Before World War II, over 50% of platinum was used in jewelry. Now about 90% of the consumed platinum is used in industry and science. The use of platinum in medicine is also growing.
Acid-resistance, heat-resistance and constancy of properties upon ignition have made platinum absolutely indispensable in the production of laboratory equipment. From platinum they make: crucibles, cups, glasses, spoons, spatulas, spatulas, tips, filters, electrodes. Platinum glassware is used for particularly precise and responsible analytical operations.
The use of platinum in technology
The most important areas of application of platinum were the chemical and oil refining industries. About half of all platinum consumed is now used as catalysts for various reactions.
Platinum is the best catalyst for the oxidation of ammonia to nitric oxide NO in one of the main processes for the production of nitric acid.
Platinum catalysts are used in the synthesis of vitamins and some pharmaceuticals.
Platinum catalysts accelerate many other practically important reactions: hydrogenation of fats, cyclic and aromatic hydrocarbons, olefins, aldehydes, acetylene, ketones, oxidation of SO2 to SO3 in sulfuric acid production.
Using platinum catalysts, catalytic reforming units produce high-octane gasoline, aromatic hydrocarbons and technical hydrogen from gasoline and naphtha oil fractions.
The automotive industry uses the catalytic properties of this metal - for afterburning and neutralization of exhaust gases.
Platinum is indispensable for modern electrical engineering, automation and telemechanics, radio engineering and precision instrumentation. It is used to make fuel cell electrodes.
An alloy of platinum and rhodium is used to make spinnerets for the production of glass fiber.
Platinum and its alloys serve as an excellent corrosion-resistant material in chemical engineering. Equipment for the production of many highly pure substances and various fluorine-containing compounds is coated with platinum from the inside, and sometimes entirely made of it.
Platinum and its alloys are also used to make:
— special mirrors for laser technology;
— heating elements of resistance furnaces;
- anode rods for corrosion protection of submarine hulls;
— insoluble anodes in electroplating;
— galvanic coatings;
- permanent magnets with high coercive force and residual magnetization (platinum alloy - cobalt PlK-78).
- electrodes for the production of perchlorates, perborates, percarbonates, peroxodisulfuric acid (in fact, the use of platinum determines the entire world production of hydrogen peroxide).
The use of platinum in medicine
A small part of platinum goes to the medical industry. Surgical instruments are made from platinum and its alloys, which, without oxidizing, are sterilized in the flame of an alcohol burner. Alloys of platinum with palladium, silver, copper, zinc, nickel serve as an excellent material for dentures.
The inertness of platinum to any compounds, its electrical conductivity and non-allergenicity make it possible to actively use it in biomedicine as a component of electrical stimulators, catheters and other medical equipment.
Certain platinum complexes are used in chemotherapy and show good antitumor activity for a small number of tumors.
The use of platinum in jewelry
Every year, the world jewelry industry consumes about 50 tons of platinum. Most platinum jewelry items in the trade contain 95% pure platinum. It has a minimum of impurities, so it is so pure that it does not fade, does not change color and retains its shine for many years.
The brilliant luster of platinum best reflects the true brilliance of diamonds, is the perfect setting for gemstones, and pairs well with natural yellow tones of gold. Due to its purity, it does not irritate the skin, since, unlike some other metals, it does not contain allergenic impurities.
The most important feature of platinum is durability. Silver and gold jewelry can wear out and have to be sent in for repairs to replace the worn part with new metal. Products made of platinum do not wear out, they are practically timeless.
INVESTING IN PLATINUM
The rarity of platinum and the high demand for it make this metal an attractive investment. Investing in platinum is a powerful financial instrument that, if used skillfully, can significantly increase your capital. This is an expensive status metal, which is widely used in industry. It is the growing demand for platinum that is the main reason for the steady growth in its prices.
Platinum is a commodity: it is traded on the London Metal Exchange and the New York Stock Exchange. In addition to platinum with immediate delivery, there are futures contracts. Prices are in troy ounces.
Platinum in terms of investment is a definite alternative to savings in a particular currency. In Russia, investing in precious metals, including platinum, is offered to its clients by a number of banks - Sberbank, NOMOS-Bank, SMP Bank, etc. It is possible to make transactions with physical ingots and using depersonalized metal accounts. In order to carry out such operations for their clients, banks under Russian law require a special license.
Graph of platinum price changes during 2013. The price of platinum in rubles per gram is calculated daily by the Central Bank of Russia.
Opening of depersonalized metal accounts (OMS).
OMS can be opened both by depositing physical metal (ingots) into this account, and by purchasing depersonalized metal from a bank for cash rubles or by debiting funds from a current account or a deposit account. Based on the period of functioning of the CHI, there are current and deposit accounts.
CHI on demand (current). Income is formed based on the growth of the market value of the precious metal in the account. The depositor can both withdraw funds and replenish the account. With this option, he has the opportunity to maneuver and manage his income, but this requires certain analytical skills.
OMS urgent (deposit). The term of savings savings on deposit MHI is fixed, it is negotiated when opening an account and varies from bank to bank. Income is generated from interest that is accrued in grams of the precious metal and the dynamics of precious metals quotations on world markets over this period. It may turn out that during the expiration of the contract, market prices will change in an unfavorable direction, and this may bring you losses.
Banks collect commission fees from customers for certain operations on the account, namely:
— for crediting the precious metal to the account upon the physical delivery of ingots;
- for the issuance of precious metal from an unallocated metal account in physical form;
- income received from changes in precious metal quotes is subject to personal income tax at a rate of 13%, the responsibility for declaring and paying tax lies with the investor.
The most serious drawback of this investment instrument and at the same time the biggest risk for the investor is the lack of compulsory compulsory health insurance. This fact requires especially careful selection of a bank for conducting compulsory medical insurance.
Buying precious coins.
The tax legislation of the Russian Federation classifies platinum coins of the Russian Federation and the USSR as commemorative, therefore, when buying these coins, you must pay VAT, which will be 18% of the value of the coin. Income from investments in precious coins is calculated as the difference between the price of the initial purchase of coins from the bank and the price of their subsequent sale to the bank.
In the Soviet Union, commemorative commemorative platinum coins were issued from 1977 to 1991. In Russia, platinum coins were issued from 1992 to 1996. Platinum coins are also issued by other states.
It is worth noting that platinum coins are very rare, they are quite difficult to find on sale, not to mention the possibility of their resale in a bank branch.
Purchase of measured bars.
The largest banks in Russia develop and approve their own rules for the sale and purchase of measured bars. These rules describe in more detail the requirements for the compliance of measured bars with standards for the admissibility of their contamination, as well as the cleanliness and integrity of the documentation accompanying them. Before buying bullion, you must carefully study these rules.
If you do not plan to take out an ingot purchased from a bank from a certified vault, but wish to transfer it for storage to the same bank by issuing a metal deposit account, then the legislation allows you not to pay the amount of VAT from the purchase.
Many experts believe that platinum is just the investment tool that you can trust and having 10 - 15% of platinum in your investment portfolio of precious metals will not be superfluous at all. But only the investor himself decides whether this type of precious metal can be useful to him or not.
It is one of the chemical elements. A metal of great value. Here is a concise answer to what platinum is. Under natural conditions, Pt occurs in the form of nuggets, it can be "pure" or with impurities.
Details
If you plunge into history, it turns out that platinum got its name thanks to the Spanish conquistadors, at that time they conquered South America. Then they mined silver and discovered a metal resembling silver, which turned out to be refractory.
No one knew how to exploit this metal - the Spaniards did not come up with anything else but to simply throw away Pt.
For a long time, the use of metal was not known. The thing is that it is a refractory element. Antoine Lavoisier was the first to melt it down in 1782. To do this, he used a device he created for supplying burning oxygen, putting there a small part of Pt, which was in charcoal. The scientists were delighted.
The Academy of Sciences in Paris could personally observe this experiment, as it was repeated. It was not easy to do this, because the scientist's apparatus had to be transported, and this required money.
Many saw it. One of the lucky ones was Count Du Nord. But in fact it was Pavel 1 (son of Catherine the Great).
Stocks
Russia also had its own platinum reserves, which were discovered in the Urals in 1819 near Yekaterinburg. Later, in 1854, deposits were found in the Nizhny Tagil district, and industrial production began. Russia has taken a leading position in the production of this metal throughout the world.
There was a great demand for Ural platinum from foreign firms. After the industry began to extract the "pure" metal, this trend only increased. Britain and France showed particular interest at first, and then Germany joined in, and the United States of America also joined.
A lot of metal was mined in the Urals, but not all of it could be exploited. That is why it was decided to create platinum coins in 1826. In addition, they began to produce other products of excellent quality. Now one coin of the 19th century can cost up to 5,000 US dollars. In Russia, they began to mint coins from the white element in 1828.
Pt stocks are currently available in the following countries:
- Zimbabwe;
- China;
- Russia;
- USA.
These 5 countries contain about 90% of the world's reserves.
It is interesting! Metal was actively exploited in ancient Egypt when creating various jewelry.
Story
It is curious that the ancient Incas mined and exploited the metal. But the Old World knew nothing about Pt. In 1557, the first news about platinum appeared. But the scammers who counterfeited the money learned an interesting property of Pt - it is perfectly alloyed with gold.
This was followed by the incredible: the Spanish king in 1735 stopped the import of metal into the country. And all its reserves, by decision of the ruler, were to be drowned in the sea.
Not only counterfeiters tried to cheat, but also jewelers. They added an element to an alloy with gold, reducing the price of the item. This process was approached responsibly - it was almost impossible to detect fraud. Platinum contributed to the increase in weight, to somehow compensate for this, they added a little silver. Nevertheless, the fraud was discovered. Therefore, the import of platinum into Europe was banned for a certain period.
public properties
In the chemical table, platinum is named Pt, its autonomous number is 78. A simple chemical element is a heavy but soft metal, its atomic mass is 195.084 amu. e. m. The color of platinum has a silvery-white tint. This is a rare valuable item. The chemical properties of platinum are unique, it is an inert metal.
Platinum's physical properties are phenomenal. To melt platinum, you need to place it where the temperature will reach 1769 degrees Celsius. And for the metal to boil, you need 3800 degrees. It becomes clear that the element has low thermal conductivity.
Platinum nuggets have an external resemblance to silver. But only the properties of silver are lower: it is lighter, prone to damage, and dissolves in nitric acid. Masters, to create products similar to platinum, use alloys including iron, nickel, chromium.
Here are more precise specifications:
It is known that platinum does not occur absolutely without impurities. Therefore, it must be separated from other metals. For this, hydrochloric and nitric acid are useful. From the resulting metal, many products can be made:
- jewelry;
- ingots;
- anode electrodes;
- laboratory glassware;
- chemical equipment.
Pt is used in many areas. This may be the chemical and electronic industries, as well as medicine. For example, refineries operate platinum catalysts.
It is used to make laboratory glassware. Improved sensors, thermometers - all this cannot exist without platinum. And in medicine, platinum has earned a special calling. It is used in medicines aimed at combating cancer.
The main advantages of platinum:
- has plasticity and malleability;
- electrical conductivity;
- high melting point;
- surpasses gold and silver in several criteria (harder, heavier);
- does not oxidize, does not react with other substances.
A good way to invest is platinum coins. At the moment, coins from this element are of particular value and uniqueness. Their face value is 12 rubles. The real price is much higher. These are coins of 1832, they are very rare and have a lot of weight.
They also attract investment in bullion. You can buy them at the Bank of Russia. The front side reflects the marking:
- country of origin (“Russia” in an oval);
- weight;
- element name;
- weight fraction / metric sample;
- manufacturer's trademark.
Two technologies for applying the inscription are used: convex, depressed.
Platinum has won the hearts of many women and men. The great Louis-Francois Cartier, the founder of the famous Cartier company, contributed to the fact that many saw the metal. It was he who claimed that this element has no analogues and is very useful in jewelry, as it has many positive properties.
But François was not the only one who admired metal. Another of his admirers was Carl Faberge. The master created author's products. It is curious that many of the ideas of Louis Francois Cartier adopted from Faberge. These include floral arrangements and animal motifs.
jewelry
The metal is of extraordinary beauty, so making jewelry from it is especially profitable. They are expensive and require careful care. Platinum is highly durable, so the fasteners made from it are practically invisible. A platinum thing can conquer a girl.
Jewelry 950 samples are made from "pure" metal, at least 95%. Care does not take much time, you only need to clean the products once a week. There are many detergents that allow you to clean metal. And if scratches appear, it is worth giving the product to the master so that he brings it to a new look (polishing).
Platinum candles for cars (Pt contacts) are popular. Metal is used as an electrical conductor. High temperature resistance, corrosion resistance and durability are the main advantages of these candles.
This metal even appeared in the famous film "Platinum Blonde". It was this film that lifted him to the peak of popularity.
Many liked the unpretentious light plot, as well as the original decorations. This film appeared in the 1930s in America. Many years have passed, but since then the popularity of metal has only increased.
The magical properties of platinum lie in its healing effects. It is believed that due to the most powerful energy, it has a positive effect on human health.
Preparations with this metal are used in medicine, since its molecules are capable of much. But not everyone can afford such drugs.
It becomes clear why Pt was able to win the love of people around the world. It's all about the specific characteristics. This metal can be used in production, or it can be used to decorate the hand of a beautiful girl. Investors also cannot resist platinum, because investing in it is the road to the future.
Platinum is a chemical element, a metal (the formula of platinum is Pt), and, moreover, very rare. However, this does not negate a wide range of its applications - from jewelry to pacemakers.
Platinum is a precious metal that is included in the so-called transitional group, making up the company of gold, silver and copper. According to its atomic structure, platinum is able to easily bond with other elements.
The history of the discovery and the origin of the name of the metal
The first mention of this substance dates back to 1557, when the Italian physician and humanist Julius Caesar Scaliger described the metal he found in Central America. It was not possible to melt this metal with the means and methods that existed at that time and were available to the Spanish conquistadors. Therefore, Scaliger called the new chemical substance platinum, which can be translated as "little silver" or even "silver".
This name reflected both the color of the metal (silver-white) and its practical uselessness to the people of that era. Therefore, in the beginning, ancient metallurgists in Egypt and America used the metal to make jewelry and decorative items, mixing it with more fusible gold. Perhaps that is why the metal was called white gold for a long time. The analogies were obvious - it, like gold, proved to be extremely resistant to tarnishing and corrosion. On the other hand, the element is very plastic and malleable: it can be easily deformed, drawn into a wire, etc. Finally, platinum is a full-fledged noble metal, since it does not oxidize and is not exposed to common acids.
Finding in nature. isotopes
World reserves of platinum are small. The metal content in the earth's crust is 5 · 10-7 wt.%. It is found both in pure form and in compounds. The most important minerals are polyxene, which contains 6 ... 10% iron, as well as palladium platinum, ferroplatinum, iridoplatinum, sperrylite PtAs2, as well as a number of more complex chemical compounds, including sulfur, palladium. The best known of these minerals is braggite. It occurs together with and iron pyrites in contact with gold ore, crystallizing in a cubic or, more rarely, an octahedral form. Braggite has a metallic luster and also contains traces of rhodium and antimony.
To date, scientists have discovered quite a few isotopes of this element: 6 natural and 37 artificial. The most common isotopes:
- Pt195 (33.83% of the total).
- Pt194 (32.97% of the total).
- Pt196 (25.24% of the total).
- Pt198 (7.16% of the total).
- Pt192 (0.78% of the total).
- Pt190 (0.01% of total).
Field
Platinum mining in the world is concentrated in South Africa (80% of the world's production), Russia and Canada. Latin American platinum only reached Europe in 1735. The metal has also been found in Brazil in the mineral syenite, where it is found along with gold.
Where is platinum mined? Among the largest deposits:
- Ural alluvial deposits found in the Nizhny Tagil region;
- Lapland mines (Finland), where the metal is in a bound state together with diamonds;
- Deposits in the Canadian provinces of Ontario and British Columbia, as well as in vast areas adjacent to the Yukon Valley.
Deposits of platinum in Russia, in addition to the Urals, are also located beyond the Arctic Circle, in the region of Norilsk. Germany (the Rhine Valley), Indonesia (the island of Borneo), Spain, Ireland, the USA, Australia and New Zealand are also formally considered countries for the extraction of platinum. The volume of production there is small and does not yet have world economic significance.
Of the exotic methods of obtaining, it is worth mentioning meteoric iron, which often contains this metal.
Extraction and production technologies
How is platinum mined? The method of extraction is determined by the form of finding platinum in nature, in the feedstock. For example, most of the platinum ore mined in British Columbia is coarse and in the form of nuggets found in relatively small areas. Nuggets in their weight rarely exceed half an ounce (14 grams). Most of the metal occurs in small grains, which are separated by platinum producers into magnetic and non-magnetic. The latter make up a large proportion of the total.
Pure metal often contains traces of nickel, as evidenced by spectrochemical studies of samples from Russia, Spain and America. For example, when platinum is mined in Russia, samples from Kitlim contain at least 0.1% nickel, and Nizhny Tagil magnetic raw materials contain up to 0.75% nickel.
Physical properties
The element is one of the densest - 21,450 kg / m3, which is more than 21 times the density of water or 6 times the density of diamond. Among the main properties of this metal:
- The atomic weight is 195.1.
- Melting point -1768.4 0С.
- The boiling point is 3825 0C.
For industrial applications, the magnetic properties of a given metal matter. The non-magnetic form is more common, it has an increased density. Magnetic properties are determined by the presence of . Interestingly, some samples of the Ural platinum attract iron filings more strongly than an ordinary magnet.
Chemical properties
The first chemical studies were carried out as early as 1741 by the British scientist Charles Wood. It was he who first called this element a metal (the eighth among those known at that time), and described some of the characteristics of platinum.
Reactivity
The history of platinum includes testing for "nobility". The metal passed it thanks to the research of British chemists William Wollaston and Smithson Tennant. At the beginning of the 19th century, they tried to dissolve purified platinum in a mixture of nitric and hydrochloric acids. After the metal was separated from the rest of the solution, palladium, rhodium, osmium, iridium, and later ruthenium were found in the waste. It is characteristic that today mining is carried out according to a similar technology: samples containing the element are dissolved in an acidic environment, separated from the rest of the solution and by-products, and melted at very high temperatures to obtain pure metal.
Platinum cylinders have long been used as the international standard for measuring weight. Now the metal is used to create high-strength parts for various machines, tools and jewelry. Due to its very low level of reactivity, the element is used in some anti-cancer drugs.
According to the latest data, about half of cancer patients use platinum-containing drugs, since the antitumor properties of platinum are already well understood. The metal is also used in pacemakers, dental crowns, and other devices due to its high resistance to corrosion from body fluids and lack of reactivity to vital functions.
Where else is platinum used? In combination with cobalt, this metal is used to create strong permanent magnets that are used in clockwork, motors, and medical equipment.
Approximately one third of the world's consumption of platinum as a precious metal falls on jewelry. In particular, most large diamonds are inserted into platinum cases.
Catalysts
Nearly half of the platinum mined is used in catalytic converters - vehicle components that reduce the toxicity of exhaust gases to acceptable levels. They can withstand the high temperatures required for oxidation reactions, during which the toxicity of emissions is reduced. In addition, platinum is used as a catalyst in the production of fertilizers, plastics and gasoline.
monetary functions. Marks of Excellence
Since platinum is a precious metal, in many countries it is stored in the form of bars that can be used for interbank payments. Commemorative signs are also produced. However, due to limited reserves, the volume of production of such items, in comparison with gold or silver, is small.
Platinum price and forecast for 2018
Annual production does not exceed 120…130 tons. Investment activity in the market is determined by significant price fluctuations (see ?). How much is platinum worth? Starting from February 2018, the cost of platinum has been falling, and, according to experts, it is predicted at the level of 29…32 per gram. However, the exchange rate of platinum and the dynamics of prices in recent years are seasonal: by the summer, the price of the metal usually increases. The forecast for platinum for 2018 shows that the investment risks from investing are quite high: over the past 6 years, the price of a gram of this metal has almost halved: from 59 to 31 US dollars per gram.
Interesting Facts:
- The largest platinum nugget ever found weighed 7837 g.
- In his research, Wood relied on the documents of the Spanish scientist and naval officer Antonio de Ulloa confiscated by the British Navy, which date back to 1735.
- The element was first discovered in the alluvial deposits of the Pinto River, which flows through the territory of Colombia.
Among all noble metals, platinum occupies a special place and its value is higher in comparison with gold and silver. The fact is that the extraction of this substance is a rather laborious process, and it is not common. The higher cost of Platinum is at least due to the fact that about 10 tons of rock have to be processed to obtain one ounce. In turn, to create a similar amount of gold, about 3 tons of ore is spent.
History of metal
Even before our era, people knew about the metal platinum, for example, the ancient Egyptians used it to make jewelry. It was widely used by the Indians of the Inca tribe, but was gradually forgotten. The latest history of mining and processing of platinum dates back to the period of the development of America by the Spanish conquistadors.
However, at first, due attention was not paid to the metal, as evidenced even by its name - in Spanish, the word means “little silver”. Often it was considered unripe gold at all and was thrown away. It's a pretty tough metal., which has a high density index, which significantly complicates its processing.
Among the properties of the metal, it is worth noting the most unique:
- When heated to temperatures below 200 degrees, it is not subject to oxidation and does not enter into chemical interaction with other substances.
- Indicators of hardness and density are higher in comparison with gold and even more so with silver.
- Differs in high plasticity and well gives in to forging.
- It has excellent electrical conductivity.
- Does not interact with acids, except aqua regia.
- It has a high melting point of 1768.3 degrees.
The metal in its pure form is practically not found in nature, and if we talk about what platinum consists of, then most often it is alloys with rhodium, palladium, iron, iridium and some other substances.
The rate of oxidation depends on the pressure of oxygen and the rate of its supply to the metal surface. Since most often it is mined in the form of alloys, the presence of other substances in them slows down this process.
The most common oxides are:
The resistivity of platinum is relatively small, but in terms of electrical conductivity, it is inferior to aluminum, silver, and copper. At the same time, during heating, the resistivity index increases, and the conductivity decreases accordingly. Scientists explain this fact by the fact that as the temperature increases, the particles that make up platinum begin to move randomly and, as a result, the passage of current becomes difficult.
The industry actively uses the ability of platinum to accelerate various chemical reactions, which makes it an excellent catalyst.
Application area
In medicine, metal compounds, mainly amminoplastinates, are used in the treatment of various forms of cancer. Cisplastin was the first such drug, but oxaliplatin and carboplatin are currently the most popular. The use of metal in technology is much wider. If we talk about where platinum is contained, the main directions can be noted:
From about the middle of the XVIII century in Russia, platinum performed a monetary function. Exactly the first platinum coins were made in the Russian Empire, but it happened in 1828. Currently, some states continue to mint coins of various denominations, but they are most often used for investment. It should also be said about the jewelry industry, which annually consumes about 50 tons of metal. Platinum jewelry is most popular in Japan.