Platinum

Characteristics and Properties of Platinum

• Lustrous, ductile, and malleable, silver-white metal
• More ductile than gold, silver, or copper
• Well-suited for industrial applications due to physical characteristics and chemical stability
• Excellent resistance to corrosion
• Well-suited for use in fine jewelry due to resistance to wear and tarnish
• Silvery white appearance
• Standard atomic weight of 195.084±0.009
• Boiling point of 4098K (3825°C, 6917°F)
• Density of 21.45g/cm³ (near room temperature)
• Mohs hardness of 3.5
• Forms a thin surface film of PtO that can be easily removed
• Common oxidation states of +2 and +4
• Reacts with chlorine, bromine, iodine, and sulfur
• Insoluble in hydrochloric and nitric acid, but dissolves in hot aqua regia

Occurrence and Production of Platinum

• Extremely rare metal, occurring at a concentration of only 0.005 ppm in Earth's crust
• Often found as native platinum or alloyed with other platinum-group metals and iron
• Secondary deposits in alluvial deposits, such as in Colombia and the Ural Mountains, Russia
• Also found in nickel and copper deposits as sulfides, tellurides, antimonides, and arsenides
• Major source of platinum associated with nickel ores in the Sudbury Basin deposit in Ontario, Canada
• Bushveld Igneous Complex in South Africa contains around 75% of the world's known platinum
• Norilsk in Russia and Sudbury Basin in Canada are other large deposits
• Smaller reserves can be found in the United States, for example in Montana
• South Africa was the top producer of platinum in 2010, followed by Russia
• Large platinum deposits are present in Tamil Nadu, India
• Platinum is obtained as a by-product from nickel and copper mining and processing
• Impurities can be removed from raw platinum by floating lighter impurities, using an electromagnet, and resisting hydrochloric and sulfuric acids
• Aqua regia is used to dissolve palladium, gold, and platinum, while other platinum-group metals remain unreacted
• Small scale recovery of platinum from laboratory residues can be done using elemental zinc

Uses and Applications of Platinum

• Catalytic converters
• Laboratory equipment
• Electrical contacts and electrodes
• Platinum resistance thermometers
• Jewelry
• Platinum is used as a catalyst in chemical reactions, especially as a catalytic converter in automobiles
• It is also used in the petroleum industry for catalytic reforming and hydrogenation of vegetable oils
• Platinum catalyzes the decomposition of hydrogen peroxide and is used in fuel cells
• Platinum has various other applications in medicine, biomedicine, glassmaking, electrodes, and turbine engines

History and Significance of Platinum

• Traces of platinum have been found in ancient Egyptian gold
• Native Americans in South America used platinum to produce artifacts
• Europeans first encountered platinum in the 16th century
• Antonio de Ulloa is credited with the discovery of platinum
• Charles Wood found Colombian platinum samples in Jamaica in 1741
• Platinum was initially assumed to be non-pliable and brittle due to impurities, but pure platinum is actually highly malleable
• Charles III of Spain provided resources to Pierre-François Chabaneau, who succeeded in producing pure, malleable platinum
• From 1889 to 1960, the meter was defined as the length of a platinum-iridium alloy bar known as the international prototype meter
• The kilogram was defined as the mass of the international prototype of the kilogram, a platinum-iridium alloy cylinder made in 1879
• Platinum is used in the standard hydrogen electrode due to its corrosion resistance
• Platinum Resistance Thermometry (PRT) has industrial applications and standards such as ASTM E1137 and IEC 60751
• Platinum is considered prestigious in the jewelry trade
• Platinum coins, bars, and ingots are collected and traded
• Platinum is valued as an investment for its scarcity and industrial applications

Miscellaneous Facts about Platinum

• Platinum wire is commonly used for electrodes in laboratories
• Thermogravimetric analysis utilizes platinum pans and supports due to their chemical inertness at high temperatures
• Platinum is used as an alloying agent in the production of fine wires, noncorrosive laboratory containers, medical instruments, dental prostheses, electrical contacts, and thermocouples
• Platinum-cobalt, an alloy of platinum and cobalt, is used to create strong permanent magnets
• Platinum-based anodes find applications in ships, pipelines, and steel piers
• Platinum is associated with exclusivity and wealth in advertising due to its rarity
• Platinum is used in jewelry as a 90-95% alloy for its inertness and inherent bullion value
• Platinum is used in watchmaking for its resistance to tarnishing and wear compared to gold
• Short-term exposure to platinum salts can cause irritation of the eyes, nose, and throat
• Long-term exposure to platinum may lead to respiratory and skin allergies
• Platinum is a precious metal commodity traded as bullion with the ISO currency code of XPT

Platinum Mentions

Platinum Data Sources