Platinum (Pt)

A unique and rare precious metal, platinum is both attractive and useful in a wide range of scientific, chemical, medical and electronic applications. In South America, platinum was used for decorative purposes, and it adorned Egyptian tombs from 700 BC. Several European and South American scientists, geologists and explorers contributed to the extraction and production of pure platinum in the 18th century, but it was the discovery of the Bushveld complex, a large platinum deposit in South Africa, that made exclusive extraction economically viable. Today, platinum is an extremely valuable element and also an investment instrument traded in the US and the UK.

Physical and Chemical Properties

Platinum is a dark gray color with a metallic luster. It is dense, soft (its hardness rates 3.5-4.5 on the Mohs scale), malleable and ductile. It conducts electricity and heat well. At room temperature it is solid, and melts at 1768.2°C. Because platinum is completely non-toxic and hypoallergenic, it is considered biologically compatible for medical use and may even inhibit cancer cell growth. As platinum resists corrosion and remains stable under high temperatures, it is frequently used as a catalyst.

Production and Processing

Platinum is found naturally in alluvial placer deposits, but for economic reasons, platinum group metals are most often mined from two types of ore: cooperite and sperrylite. In rare locations, such as in South Africa’s large Bushveld complex, it makes economical sense to extract pure platinum from ore. In other locations, platinum is simply extracted from copper and nickel as a byproduct. The extraction process involves crushing, froth flotation, skimming, drying, heating, application of chemical and electrolytic measures, dissolution in aqua regia, chemical conversion and burning. Fortunately, once extracted, platinum can also be recycled.

Applications

Platinum is in high demand due to its aesthetic and decorative applications: it is used in jewelry and alloyed to produce white gold. The medical industry has made exciting breakthroughs using platinum in medical equipment, devices, dental fillings and prescription drugs. Used as a catalyst, platinum is mostly found in vehicle catalytic converters that reduce toxic exhaust chemicals, and also in fuel cells to increase efficiency. Lasers, magnetic hard disks, thermocouples and switch contacts contain platinum parts, and platinum coats capacitors, fuel nozzles in jet engines and nose cones in missiles. LCD and optical fiber components also contain platinum.

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Wedding bands made of platinum are valued for their high-strength, scratch-resistance, and durability.  

 

Sources

Advantages

  • Attractive metallic gray color
  • Non-toxic, hypoallergenic and biocompatible
  • Corrosion-resistant
  • An effective catalyst
  • Heat, cold and wear-resistant