[plat-n-uh
m, plat-nuhm] 
| 1. | Chemistry. a heavy, grayish-white, highly malleable and ductile metallic element, resistant to most chemicals, practically unoxidizable except in the presence of bases, and fusible only at extremely high temperatures: used for making chemical and scientific apparatus, as a catalyst in the oxidation of ammonia to nitric acid, and in jewelry. Symbol: Pt; atomic weight: 195.09; atomic number: 78; specific gravity: 21.5 at 20°C. |
| 2. | a light, metallic gray with very slight bluish tinge when compared with silver. |
| 3. | made of platinum. |
| 4. | (of a record, CD, or cassette) having sold a minimum of one million copies. |
| plat·i·num (plāt'n-əm) n.
[New Latin, from Spanish platina, platinum; see platina.] |
Platinum
An element that is sometimes used in jewelry or as a catalyst in electronics.
Investopedia Commentary
Platinum is considered to be a precious metal.
See also: Bullion, Precious Metal
platinum plat·i·num (plāt'n-əm)
n.
Symbol Pt
A ductile malleable metallic element usually occurring mixed with other metals such as iridium, osmium, or nickel and used as a catalyst and in dentistry. Atomic number 78; atomic weight 195.08; melting point 1,768°C; boiling point 3,825°C; specific gravity 21.45; valence 2, 3, 4.
| platinum (plāt'n-əm) Pronunciation Key
Symbol Pt A soft, ductile, malleable, silver-white metallic element that usually occurs with osmium, iridium, palladium, or nickel. It has a high melting point and does not corrode in air. Platinum is used as a catalyst and in making jewelry, electrical contacts, and dental crowns. Atomic number 78; atomic weight 195.08; melting point 1,772°C; boiling point 3,827°C; specific gravity 21.45; valence 2, 3, 4. See Periodic Table. |
