Thursday, August 23, 2012

Platinum: The World’s Most Versatile Precious Metal?


Given that its uses now transcend as mere bling in the jeweler’s world, does platinum today truly qualify as the world’s most versatile precious metal? 

By: Ringo Bones 

Lately, platinum gained the mainstream media’s attention when in August 16, 2012, when 34 striking mine workers over a wage dispute in a Lonmin owned platinum mine located in the town of Marikana, South Africa got shot and killed by the local police force. The news of the class sent the global price of platinum rising to 30 US dollars per troy ounce during that day’s trading. Given that South Africa supplies 75% of the world’s platinum needs, the striking workers’ demands for pay raise can only be described as fair. And for some time now, gold has been more expensive than platinum – as by August 17, 2012 platinum prices hovered in the 1,450 US dollars per troy ounce mark as opposed to gold’s 1,600 US dollars per troy ounce level. Given that platinum may soon again be more expensive than gold, will platinum’s price premium truly justified by its title as the world’s most versatile precious metal?  

 Platinum, named after platina or little silver is the most abundant and most used member of the platinum metal family, which includes iridium, osmium, palladium, rhodium and ruthenium. Placed in the second transition metals region of the Periodic Table of elements, ancient artifacts made of metallic platinum have been unearthed. Though platinum wasn’t known as a distinct metal until 1557 when it was discovered in Mexico by the Italian poet and adventurer named Julius Caesar Scaliger. In 1741, the first sample of the metal was bought to Europe by an English metallurgist named Charles Wood. 

The world’s leading producer of platinum is the Republic of South Africa while other major producers are Canada, Russia and former Soviet states in Central Asia. Platinum occurs in both native – as in elemental state and in compounds. In its native state, It is usually occurs in sandlike grains in placer deposits with similar grains of the other metals of its family or with copper, cobalt, nickel or gold ores. However, large nuggets of platinum have also been found. The most important of the platinum ores are sperrylite – platinum arsenide, and cooperlite – platinum sulfide. 

Platinum is the last element in Group VIIIA of the Periodic Table. It is a silvery metal, soft, dense very ductile and malleable, and with a high tensile strength. Its electrical conductivity is comparatively low, and its coefficient of expansion is the lowest of the commercially produced metals. Platinum is untarnished by air, but vaporizes appreciably at red heat. The halogens, including fluorine, have no effect at ordinary room temperature and single mineral acids do not dissolve platinum. Aqua Regia (a mixture of nitric and hydrochloric acid) and a mixture of hydrochloric and chloric acids dissolve the metal. It is also attacked at high temperatures by fused nitrates, acid sulfates, hydroxides, peroxides, sulfides, iodine, phosphorous, arsenic, carbon, silicon, selenium and tellurium. 

At present, most of the platinum commercially produced not destined for jewelry use go into the making of catalytic converters in modern automobiles where they remove most of the nitric and sulfuric oxides found in car exhausts. Because of its relative chemical inactivity, platinum, both as a free metal and alloyed with rhodium, is an almost indispensable material for such devices as magneto contacts, spark-plug electrodes, radar parts and in critical analog computer components of World War II era bombsights. In the chemical – as in petrochemical – industries, platinum and its alloys are essential catalysts – for example in making nitric acid from ammonia; As spinnerets and bushings in the production of rayon and glass fiber; As electrodes in industrial processes involving anodic oxidation – as in producing perchlorates and peroxides and electrodeposition of nickel and rhodium and for corrosion and heat-resistant treatment of measuring and recording devices. In addition, platinum has been used extensively in jewelry, dentistry, X-Ray equipment, laboratory apparatus, medical and surgical instruments and heating units (bomb calorimeters). 

4 comments:

  1. Remember the days when platinum used to cost three times as much as gold on a troy-ounce basis? Those poor underpaid platinum miners at Lonmin's Marikana mine will never get a square deal.

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  2. Even though platinum has never been more than 500 US dollars cheaper than gold on an per Troy ounce price basis - platinum is actually 100 times more scarce than gold in the Earth's crust.

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  3. Platinum wire resistance thermometers are slowly replacing mercury filled thermometers that are toxic to our health.

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  4. The active component of those new digital read-out thermometers commonly used to tell whether one has a fever or not uses a platinum resistance wire as the active temperature measuring component instead of toxic mercury.

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