Platinum

The word platinum comes from the Latin term platina, which means silver. Platinum is a soft metallic element that is rarely found naturally pure. It often bonds with iron, silver, gold, copper or nickel. In some cases deposits of platinum with small impurities of iron have been found to be magnetic. Platinum has a hardness of 4 - 4.5 on the mohs scale of hardness, and is very malleable. Platinum streaks steel gray and is very dense with a specific gravity of 21.4 . It naturally forms into isometric cubes, but due to its high level of malleability it is rarely found in that form and more commonly found in nuggets or as grains. The most distinguishing characteristics of platinum is its heavy weight and it's occasional weak magnetism.

Platinum plays a key role in medical technology and technology in general. Platinum is used to make surgical implements as well as jewelry and is also used as a standard of weight. Platinum makes a good catalyst because it is very insoluble, and has a high melting point. This allows it to bring about chemical reactions without entering itself. This property makes it useful in the manufacturing of sulfur and in vehicle anti-pollution devices. Platinum is only soluble in heated aqua regia. It is a good conductor of heat and electricity and due to these properties has been used in the making of computer chips.

Platinum is commonly found in sands and gravels, as well as near and in rivers. The worlds best resource of platinum is found in the Russian Ural Mountains. Other significant sources include Alaska, Canada, South Africa, Columbia and Peru. The purest platinum crystals have been found in the Urals which is also the largest deposit of platinum.

Platinum is closely associated with silver. They both are silver-white in color, they both are good conductors of heat and electricity, they both streak silvery white or gray and they both can be found in cubic form(though that is very rare). The two can be easily confused while in the field but there are some key differences to look for. For one, a platinum nugget is more than double the weight of an equally sized silver nugget (since silver's SG is not but 10.5, while platinum's SG is 21.4). Also, silver tarnishes with contact to the atmosphere, while platinum does not

Since platinum is metallic and it naturally doesn't tarnish, it is ideal for jewelry. But it's level of malleability requires that it be mixed with other elements like nickel and copper to ensure that it will maintain the intended form. Jewelry made from platinum is very glamourous and very popular. Platinum jewelry may be preferred over silver jewelry because it remains brilliant and shiny, while silver jewelry has less glint.

Bibliography

I. Pellant, Chris - Rocks and Minerals

New York: DK publishing, 1992

II. R.F. Symes and R.R. Harding Crystal and Gem

New York: DK publishing, 1991

III. Wesley, Charles The Audubon Society Field Guide to North American Rocks and Minerals

New York: DK publishing, 1979

IV. Hall, Cally Gem Stones

Boston: DK publishing, 1994