Platinum and Its Use

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Physical Properties and Chemical Characteristics

Platinum (Pt, atomic number 78) is a dense, malleable, ductile, precious gray-white transition metal. Found in extremely low concentrations of 0.003 ppm in Earth's crust, it was first discovered in South America, with its name derived from the Spanish term "platina del Pinto" (little silver of the Pinto River). Discovered by Ulloa in 1753 and Wood in 1741, this metal was initially used by pre-Columbian Indians.

As a Group 10 element, platinum demonstrates remarkable resistance to corrosion and occurs naturally in nickel and copper ores. It's typically found alongside other precious metals including iridium, osmium, palladium, ruthenium, and rhodium in alluvial deposits of the Ural Mountains, Colombia, and various Western American states.

Chemical Properties and Isotopes

Pure platinum exhibits a beautiful silvery-white appearance with exceptional malleability and ductility. Its coefficient of expansion closely matches that of soda-lime-silica glass, making it ideal for sealed electrodes in glass systems. While the metal resists oxidation at any temperature, it can be corroded by halogens, cyanides, sulfur, and caustic alkalis. Though insoluble in hydrochloric and nitric acid individually, it dissolves in aqua regia to form chloroplatinic acid (H₂PtCl₆).

Figure 1. Platinum demand by application in 2006

Industrial Applications

Automotive and Environmental

The most significant application of platinum is in catalytic converters, where it transforms harmful emissions into harmless substances. Approximately half of newly mined platinum serves this purpose, with demand increasing due to stricter global emission standards.

Jewelry and Precious Metals

Platinum jewelry accounts for approximately 25% of total platinum demand. Its durability, purity (95% in Europe and USA), and resistance to tarnish make it ideal for fine jewelry and settings for precious stones.

Technology and Electronics

In the technology sector, platinum plays a crucial role in:

• Hard disk drive coatings
• Fiber optic cables
• Thermocouples
• Multi-layer ceramic capacitors

Additional Applications

• Petroleum refining
• Medical devices and anti-cancer drugs
• Fuel cells (PEM)
• Investment vehicles
• Glass manufacturing
• Chemical processing

Market Value and Investment

Platinum maintains significant value as both an industrial metal and an investment vehicle. With the ISO currency code XPT, its price fluctuates according to market forces. Its value is supported by its relative scarcity, historical performance, and fundamental industrial importance.