Platinum is the most important of the group of elements called the platinum metals, the other members of which are ruthenium, rhodium, palladium, osmium, and iridium. Platinum metals were probably used in alloyed forms in ancient Greece and Rome and were first mentioned in European literature in the early 16th century. The separation of the other platinum metals from platinum and from each other was accomplished in the early 19th century. Platinum is mined all over the world.  In the late 1980s, the Soviet Union and South Africa were the leading producers. Other leading producers are Canada, Colombia, and the United States.

Platinum is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River“ It is dense,

malleable, ductile, precious, gray-white transition metal. Even though it has six naturally occurring isotopes, platinum is one of the rarest elements in

the Earth's crust and has an average abundance of approximately 0.005 mg/kg. It occurs in some nickel and copper ores along with some

native deposits, mostly in South Africa, which accounts for 80% of the world production.

As a member of the platinum group of elements, as well as of the group 10of the periodic table of elements, platinum is generally unreactive. It exhibits a remarkable resistance to corrosion, even at high temperatures, and as such is considered a noble metal. As a result, platinum is often found chemically uncombined as native platinum. Because it occurs naturally in the alluvial sands of various rivers, it was first used by pre-ColumbianSouth American natives to produce artifacts. It was referenced in European writings as early as 16th century, but it was not until Antonio de Ulloapublished a report on a new metal of Colombianorigin in 1748 that it became investigated by scientists.

Platinum is used in catalytic converters, laboratory equipment, electrical contacts and electrodes, platinum resistance thermometers, dentistry equipment, and jewelry. Because only a few hundred tonnes are produced annually, it is a scarce material, and is highly valuable and is a major precious metal commodity. Being a heavy metal, it leads to health issues upon exposure to its salts, but due to its corrosion resistance it is not toxic as a metal. Some of its compounds, most notably cisplatin, are applied in chemotherapy against certain types of cancer.

Name: Platinum Symbol: Pt Atomic Number: 78 Group: 10 Period: 6 Atomic Mass: 195.078 amu Melting Point: 1772.0 °C (2045.15 K, 3221.6 °F) Boiling Point: 3827.0 °C (4100.15 K, 6920.6 °F) Number of Protons/Electrons: 78 Number of Neutrons: 117 Classification: Transition Metal Crystal Structure: Cubic Density @ 293 K: 21.45 g/cm3 Color: silverish

platinum

Atomic Radius : 1.83ÅAtomic Volume: 9.1cm3/molCovalent Radius: 1.3ÅCross Section (Thermal Neutron Capture) σa/barns: 0.96 Crystal Structure: Cubic face centered Electron Configuration: 1s2 2s2p6 3s2p6d10 4s2p6d10f14 5s2p6d9 6s1

Electrons per Energy Level: 2,8,18,32,17,1 Ionic Radius: 0.625Å Filling Orbital: 5d9 Number of Electrons (with no charge): 78 Number of Neutrons (most common/stable nuclide): 117 Number of Protons: 78 Oxidation States: 2,4 Valence Electrons: 5d9 6s1

Number of Energy Levels: 6 First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18Fourth Energy Level: 32 Fifth Energy Level: 17Sixth Energy Level: 1

Isotope Half Life

Pt-188 10.2 days

Pt-190 6.0E11 years

Pt-191 2.96 days

Pt-192 Stable

Pt-193 60.0 years

Pt-193m 4.33 days

Pt-194 Stable

Pt-195 Stable

Pt-195m 4.02 days

Pt-196 Stable

Pt-197 18.3 hours

Pt-197m 1.59 hours

Pt-198 Stable

Characteristic

Isotopes

Occurrence

Compounds

PHYSICAL CHEMICAL

As a pure metal, platinum is silvery-white, lustrous, ductile, and malleable. It does not oxidize at any temperature, although it is corroded by halogen, cyanides, sulfur, and caustic alkalis. Platinum is insoluble in hydrochloric and nitric acid, but dissolves in aqua regia to form chloroplatinic acid, H2PtCl6. Platinum's resistance to wear and tarnish is well suited for making fine jewelry. The metal has an excellent resistance to corrosion and high temperature and has stable electrical properties. All of these characteristics have been exploited for industrial applications.

Platinum dissolves in hot aqua regia

The most common oxidation states of platinum are +2 and +4. The +1 and +3 oxidation states are less common, and are often stabilized by metal bonding in bimetallic (or polymetallic) species. As is expected, tetracoordinate platinum(II) compounds tend to adopt 16-electron square planar geometries. While elemental platinum is generally unreactive, it dissolves in aqua regia to give soluble hexachloroplatinic

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Platinum has six naturally occurring isotopes: 190Pt, 192Pt, 194Pt, 195Pt, 196Pt, and 198Pt. The most abundant of these is 195Pt, comprising 33.83% of all platinum. It is the only stable isotope with a non-zero spin; with a spin of 1/2, 195Pt satellite peaks are often observed in 1H and 31P NMR spectroscopy (i.e. Pt-phosphine and Pt-alkyl complexes). 190Pt is the least abundant at only 0.01%. Of the naturally occurring isotopes, only 190Pt is unstable, though it decays with a half-life of 6.5×1011 years. 198Pt undergoes alpha decay, but because its half-life is estimated at longer than 3.2×1014 years, it is considered stable. Platinum also has 31 synthetic isotopes ranging in atomic mass from 166 to 202, making the total number of known isotopes 37. The least stable of these is 166Pt with a half-life of 300 µs, while the most stable is 193Pt with a half-life of 50 years. Most platinum isotopes decay by some combination of beta decay and alpha decay. 188Pt, 191Pt, and 193Pt decay primarily by electron capture. 190Pt and 198Pt have double beta decay paths.back

A native platinum nugget, Kondyor mine, Khabarovsk Krai

Platinum is an extremely rare metal,occurring at a concentration of only 0.005 ppm in the Earth's crust.It is sometimes mistaken for silver (Ag). Platinum is often found chemically uncombined as native platinum and alloyed with iridium as platiniridium. Most often the native platinum is found in secondary deposits; platinum is combined with the other platinum group metals in alluvial deposits. The alluvial deposits used by pre-Columbian people in the Chocó Department, Colombia are still a source for platinum group metals. Another large alluvial deposit is in the Ural Mountains, Russia, and it is still mined.

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In nickel and copper deposits, platinum group metals occur as sulfides (e.g., (Pt,Pd)S), tellurides (e.g., PtBiTe), antimonides (PdSb), and arsenides (e.g., PtAs2), and as end alloys with nickel or copper. Platinum arsenide, sperrylite (PtAs2), is a major source of platinum associated with nickel ores in the Sudbury Basin deposit in Ontario, Canada. At Platinum, Alaska, about 545,000 troy ounces had been mined between 1927 and 1975. The mine ceased operations in 1990.The rare sulfide mineral cooperite, (Pt,Pd,Ni)S, contains platinum along with palladium and nickel. Cooperite occurs in the Merensk Reef within the Bushveld complex, Gauteng, South Africa.In 1865, chromites were identified in the Bushveld region of South Africa, followed by the discovery of platinum in 1906. The largest known primary reserves are in the Bushveld complex in South Africa. The large copper–nickel deposits near Norilsk in Russia, and the Sudbury Basin, Canada, are the two other large deposits. In the Sudbury Basin, the huge quantities of nickel ore processed make up for the fact platinum is present as only 0.5 ppm in the ore. Smaller reserves can be found in the United States, for example in the Absaroka Range in Montana. In 2009, South Africa was the top producer of platinum, with an almost 80% share, followed by Russia at 11%.Platinum exists in higher abundances on the Moon and in meteorites. Correspondingly, platinum is found in slightly higher abundances at sites of bolide impact on the Earth that are associated with resulting post-impact volcanism, and can be mined economically; the Sudbury Basin is one such example.

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it serves as the precursor for many other platinum compounds. By itself, it has various applications in photography, zinc etchings, indelible ink, plating, mirrors, porcelain coloring, and as a catalyst.Treatment of hexachloroplatinic acid with an ammonium salt, such as ammonium chloride, gives ammonium hexachloroplatinate, which is relatively insoluble in ammonium solutions. Heating this ammonium salt in the presence of hydrogen reduces it to elemental platinum. Potassium hexachloroplatinate is similarly insoluble, and hexachloroplatinic acid has been used in the determination of potassium ions by gravimetryWhen hexachloroplatinic acid is heated, it decomposes through platinum(IV) chloride and platinum(II) chloride to elemental platinum, although the reactions do not occur stepwise:(H3O)2PtCl6·nH2O PtCl4 + 2 HCl + (n + 2) H2OPtCl4 PtCl2 + Cl2PtCl2 Pt + Cl2All three reactions are reversible. Platinum(II) and platinum(IV) bromides are known as well. Platinum hexafluoride is a strong oxidizer capable of oxidizing oxygen.

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Platinum(IV) oxide, PtO2, also known as Adams' catalyst, is a black powder which is soluble in KOH solutions and concentrated acids. PtO2 and the less common PtO both decompose upon heating. Platinum(II,IV) oxide, Pt3O4, is formed in the following reaction:

2 Pt2+ + Pt4+ + 4 O2− → Pt3O4

Platinum also forms a trioxide, where it is present in the +4

oxidation state.

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Unlike palladium acetate, platinum(II) acetate is not commercially available. Where a base is desired, the halides have been used in conjunction with sodium acetate. The use of platinum(II) acetylacetonate has also been reported.

Several barium platinides have been synthesized in which platinum exhibits negative oxidation states ranging from −1 to −2. These include BaPt, Ba3Pt2, and Ba2Pt. Caesium platinide, Cs2Pt, has been shown to contain Pt2−anions. Platinum also exhibits negative oxidation states at surfaces reduced electrochemically. The negative oxidation states exhibited by platinum are unusual for metallic elements, and they are attributed to the relativistic stabilization of the 6s orbitals.

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Zeise's salt, containing an ethylene ligand, was one of the first organometallic compounds discovered. Dichloro(cycloocta-1,5-diene)platinum(II) is a commercially available olefin complex, which contains easily displaceable cod ligands ("cod" being an abbreviation of 1,5-cyclooctadiene). The cod complex and the halides are convenient starting points to platinum chemistry.Cisplatin, or cis-diamminedichloroplatinum(II) is the first of a series of square planar platinum(II)-containing chemotherapy drugs, including carboplatin and oxaliplatin. These compounds are capable of crosslinking DNA, and kill cells by similar pathways to alkylating chemotherapeutic agents.

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Platinum atom

ADVANTAGE LIMITATION

Always Natural colour No corrosion and dissolve by acid No rust and no melt by fire because it high

thermal more than gold Platinum is rare.  and because of its

remarkable properties, industry is constantly finding new uses for it.

Platinum often moves in the opposite direction of traditional investments, making it a good way to stabilize the value of your portfolio.

Platinum also can be attractive as a stand alone investment. 

Platinum is an excellent hedge against inflation.

Platinum is one of the most liquid of all investments. It is readily portable, easy to store, and is recognized world-wide.  It is easily and discreetly bought and sold.  It can be easily converted to cash at any time.

Because it’s very strong then harder to transform for accessory

High cost

Platinum is primarily an industrial metal. It is a critical material for many industries and is

considered a “strategic metal” by the US Government as a military resource. It is

estimated that about 20% of the products purchased by modern consumers either contain

platinum or use it in production. Total demand for platinum falls into eight broad categories

Platinum, together with palladium and rhodium, are primary elements in autocalysts that control vehicle exhausts emissions of hydro-carbons, carbon monoxide, oxides of nitrogen and particulate. Autocatalysts convert most of these emissions into less harmful carbon dioxide, nitrogen and water vapor. Autocatalyst was forecast to account for almost 51% of total platinum demand in 2006 (up from 25% in 2000).

Demand for platinum in autocatalysts started to increase significantly in the seventies when clean air legislation was introduced in USA and Japan. Many other countries followed this policy since then. However, in the 1990s, there was a substitution from platinum to palladium in autocatalysts in the United States, mainly due to its relatively lower cost and better performance in autocatalysts. In Europe platinum was more widely used since it is an essential element for diesel cars. Recent developments in the palladium market together with technological advances have led to a switch back to platinum. In recent years demand for platinum in autocatalysts has shown a considerable growth in emerging countries that introduced new environmental legislation. Demand for platinum in this application is expected to grow as stricter emissions standards and regulations are approved.

Platinum has become a very popular choice for modern jewellery, displacing significant gold demand. Its hardness and durability allows it to be used in purer form for secure stone settings. It is much superior to silver because of its resistance to oxidation and discoloration. Its rich hue and reflectivity enhances the brilliance of precious stones. Platinum is hypoallergenic which makes it the best jewellery choice for people who suffer reactions from other metals or 14k (alloyed) gold.

Platinum jewellery has been particularly popular with Asian consumers. Many Asians feel that platinum has a more pleasing contrast with the Asian skin colour than other metals. Other ethnic groups have started to purchase platinum for similar reasons. Platinum also seems to have a marketing advantage over gold or silver. Products and awards with the “Platinum” designation are typically considered superior those labelled “Gold” or “Silver”. This gives platinum jewellery items additional prestige.

Platinum is used as a catalytic agent in processing of nitric acid, fertilizers, synthetic fibers, and a variety of other materials. In catalytic processes, the catalyst material is not consumed and can be recycled for future use. This makes chemical demand for platinum quite volatile. Platinum is essential in many of these processes and there are few satisfactory substitutes.

Platinum is used in the production of hard disk drive coatings and fiber optic cables. The increasing number of personal computers will have a positive effect on platinum demand in the future. Other applications include thermocouples that measure temperature in the glass, steel and semiconductor industries or infra-red detectors for military and commercial applications. It is also used in multi-layer ceramic capacitors and crucibles to grow single crystals

Platinum is used in glassmaking equipment. It is used in the manufacturing of fiberglass reinforced plastic and of glass for liquid crystal displays (LCD). In this context, some new developments in the production of LCD glass and cathode ray tubes, both used in computer screens should be mentioned.

This is another use for the catalytic properties of platinum. The petroleum industry uses the metal in a mesh or gauze form in crude oil refining. Platinum use in petroleum refining follows global demand for refined crude oil products. Other technologies exist to perform crude oil separation but catalytic processes using platinum and palladium are much more environmentally friendly. As more refineries are built and updated, expect platinum use in petroleum refining to rise. Also, less developed countries are being pressured to improve environmental standards. Refineries in those areas will ultimately be converted to catalytic processing, further boosting demand for platinum group metals. As in other catalytic processes, platinum is not consumed and is aggressively recycled and reused. This makes petroleum industry demand highly volatile.

Platinum is seen as an attractive investment vehicle and as a good way of hedging assets against inflation. This attraction for platinum investment is spreading worldwide and is based on platinum relative scarcity, its historical price performance and unique fundamentals. Investing in platinum may be done in futures and options or in bars, ingots and bullion coins like the American Eagle, the Australian Koala or the Canadian Maple Leaf among others.

Medical

Spark plugs

Platinum is used in anti-cancer drugs and in implants. It is also used neurosurgical apparatus and in alloys for dental restorations.

Most vehicles in North America use platinum-tipped spark plugs. In Europe higher durability requirements have led to an increase in the amount of platinum used in spark plugs.

Fuel cells are devices that generate electric power. They are being developed as an alternative to internal combustion engines in vehicles. Most fuel cells apply proton exchange membrane technology producing energy from hydrogen and oxygen by using platinum catalysts. The use of fuel cells brings about environmental and economic advantages. They are more energy efficient and produce negligible pollution. All the major automotive companies, lead by Daimler-Chrysler, are planning to have fuel cell powered light vehicles by 2003-2004. Actually, there are already some fuel cell heavy vehicles working. However, the doubt remains since every vehicle using a fuel cell will be one that will not use a conventional autocatalyst. The effect on platinum demand will depend on which device uses more platinum. Present research is focusing on improving performance and reducing costs of fuel cells. Fuel cells can also provide stationary power generation. The use of platinum in fuel cells seems to be one of the platinum applications with best prospects for future demand.

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