It is used in jewelry, particularly as the setting for diamonds, in dentistry in the making of false teeth, in electrical heating apparatus, for sparking plugs in explosion motors, in the measuring of high temperatures, in electrical contacts, etc. Potassium chloroplatinate, is sometimes employed in photography.
Platinum is refined and separated from the associated platinum group metals by a somewhat complicated series of operations involving fractional crystallization or resin capture. Most platinum is recovered from primary hard rock deposits, and these are of the greatest economic importance.
Platinum is nearly always found in basic igneous rocks, such as peridotite and dunites, and in serpentine derived by alteration of such rocks. By disintegration of these rocks and concentration in stream gravels, platinum accumulates in placers. Platinum generally contains small amounts of palladium and other metals of the platinum group iridium, osmium, palladium, rhodium, and ruthenium.
These metals are closely associated in nature, almost invariably as native alloys. The most important mineral of the platinum group is sperrylite PtAs2. Sperrylite is a rare arsenide mineral, which has been found very sparingly in a limited number of localities in association with copper ore and nickel ores.
In the nickel deposits at Sudbury, Ontario, sperrylite, accompanied by palladium arsenide, forms small silvery-white cubes which are intergrown with pyrrhotite and chalcopyrite. The modes of occurrence of platinum are as follows: 1 In placers; 2 Disseminated in weakly segregated deposits of peridotite and olivine gabbro , associated with chromite ; 3 In stratified magmatic segregation deposits in basic rocks, associated with chalcopyrite and pyrrhotite with palladium ; 4 In small quantities in a very few quartz veins; 5 In contact metamorphic deposits; 6 In traces in porphyry copper deposits of many kinds with palladium ; 7 Concentrated by processes of oxidation in replacement ores of copper and gold in limestone with palladium.
Platinum and palladium ore deposits are rare, and the most extensive deposits have been found in just a few deposits. A century ago, most of the world's output of platinum was obtained from alluvial deposits in the Ural district of Russia. The native platinum in the placers forms small rounded, also concretionary and knobby dark-gray pieces.
Bright silvery scales of iridosmine occur with it. In the Ural large pieces of platinum have been found, the largest weighing about 26 pounds. In the alluvial deposits of the Urals, platinum is sometimes found associated with gold, and sometimes without gold. It is noteworthy that platinum is an original mineral formed in some peridotites; and in the Urals, where no gold occurs in the platinum-bearing gravels, these gravels can be seen to have been derived from peridotite or serpentine and the associated basic rocks.
Where gold occurs, this has been derived from different deposits in quartz veins. The platinum is associated also with chromite, another mineral which occurs frequently in peridotite and serpentine. Other minerals found associated with platinum in alluvial deposits are iridium and osmiridium. The Ural placer deposits contain on the average about 5 dwt. The most -productive of the Ural placers are those occurring along the Iss and Pura rivers, and these are said to yield about 80 per cent, of the Russian output.
In western Colombia, South America, platinum-bearing gravels occur chiefly in the Choco district ; and platinum is also found to a small extent in the gold-bearing gravels of the Barbacoas district farther south. Palladium occasionally occurs alloyed with gold. In Brazil, such palladium gold in a limestone close to the contact of an igneous rock. In Canada, platinum and palladium are obtained from the mattes obtained by smelting the nickel-copper ore of Sudbury, in Ontario.
It is famously un-reactive, and will not tarnish or rust even under the most severe circumstances. With only 0. In short, securing an adequate source of such a metal is a smart investment strategy for any properly diversified portfolio. Continue reading to learn geological facts about this precious metal and why you should consider investing.
The gold bearing sands of these three countries provides the ideal geological conditions to recover this very rare metal. In addition to gold bearing sands, deposits of platinum are often found in outcroppings of plutonic rocks like olivine and chromite. Although platinum is rare, the methods for recognizing where it is most likely located have become highly accurate, focusing on igneous deposits that show the telltale signs of prolonged heat and pressure.
Platinum is considered a Noble Metal. It is an extremely stable element used in many areas of industry. The annual supply is, on average, tons. It is the rarest of the precious metals, and its scarcity makes it an ideal commodity for investors to purchase. These long term, high energy natural processes have produced deposits of a metal so rare that if we able to collect all the platinum ever extracted in the history of mankind, it would only fill a room with 25 cubic feet of volume.
Being a malleable and ductile metal, it is ideal for jewelry, dental appliances, electrical contacts, electrical equipment, and other items that cannot suffer from oxidation or corrosion. Platinum has proven invaluable in defense projects and the automotive industries, particularly within the nose cones of missiles, jet engine parts, and catalytic converters in automobiles.
Compounds containing platinum have also proven successful in the fight against various forms of cancer like leukemia. Platinum alloys are even currently being used for building replacement valves in human hearts. From medicine to the military to motor vehicles, platinum plays a major role in human progress and survival, securing its place as a wise investment for the discerning investor.
The Earth Sciences Museum is temporarily closed until further notice. We apologize to all of our visitors and groups for this inconvenience. Thank you for your understanding. Back to Rocks and Minerals Articles. Platinum is among the rarest and most expensive of the popular precious metals. Natural platinum is fairly impure. It is always associated with small amounts of other elements gold, copper, nickel and iron and commonly contains the rare metals platinum, palladium, rhodium, iridium, osmium and ruthenium.
Platinum was regarded as an unwanted impurity in the silver they were mining and it was often discarded. Note: Platinum is typically only used where a substitute is not available as it is very rare, or for prestige. Platinum is both rarer and more expensive than gold.
It also has a very high melting temperature and it is unattached by any single acid though soluble, like gold, in a mixture of hydrochloric and nitric acids. It is an incredibly stable mineral. Platinum is a metallic white to silver-gray colour. Its streak is a shiny silver-gray. Crystals, if found, tent to be distorted cubes. Platinum has a very high specific gravity. Pure platinum would have a SG of For comparison, galena has a specific gravity of only 7.
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