Independently discovered in 1735 by Antonio de Ulloa and in 1741 by Charles Wood, platinum is named from the Spanish platina or "silver". The metal is classified as precious owing to its scarcity and commercial demand. It is very heavy and silvery white and is used in laboratory instruments, jewelry, medical and dental items, and electrical contacts. Because it is immune to air oxidation the metal is often found in native form in nature. It is sometimes found in a rare, naturally occurring alloy, platiniridium.
Naturally occurring platinum is a mixture of six non-radioactive isotopes.
Platinum is part of the the Platinum Group Metals (PGM) whic is located in the 5th and 6th rows of the transition metal section of the periodic table and includes Ruthenium, Rhodium, Palladium, Osmium, Iridium, and Platinum. Common characteristics include resistance to wear, oxidation, and corrosion, high melting points, and oxidation states of +2 to +4. They are generally non-toxic.
- Platinum has a very high melting point, so it is often used to make containers to hold molten substances.
- Jewelers use platinum as plating and decoration because of its high ductibility.
- 80-90% of platinum uses are in the industrial or metellurgical industries.
- Platinum is a catalyst in the oxidation of ammonia (to nitric oxide) in the creation of nitric acid, which is a major ingredient in fertilizers.
- An estimated 200,000 ounces of gauze consisting of 90% platinum and 10% rhodium is used in the oxidation of ammonia for the production of nitric acid.
- Regarding pollution control, platinum works as a great oxidation catalyst for removing harmful chemicals in wire enamelling, abattoirs, meat and fish processing, and in nitric oxides released in hydrocarbon reactions.
- Platinized-anodes are used in the production of elemental chlorine.