platinum

[plat-n-uhm, plat-nuhm]

noun

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. Pt; 195.09; 78; 21.5 at 20°C.

2. a light, metallic gray with very slight bluish tinge when compared with silver.

adjective

1. made of platinum.

2. (of an audio recording) having sold a minimum of one million copies.

platinum

/ ˈplætɪnəm /

noun

1. a ductile malleable silvery-white metallic element, very resistant to heat and chemicals. It occurs free and in association with other platinum metals, esp in osmiridium: used in jewellery, laboratory apparatus, electrical contacts, dentistry, electroplating, and as a catalyst. Symbol: Pt; atomic no: 78; atomic wt: 195.08; valency: 1–4; relative density: 21.45; melting pt: 1769°C; boiling pt: 3827±100°C

2. 1. a medium to light grey colour

   2. ( as adjective )

      a platinum carpet

platinum

1. 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.

2. See Periodic Table

Word History and Origins

Origin of platinum¹

1805–15; < New Latin, alteration of earlier platina < Spanish; platina

Word History and Origins

Origin of platinum¹

C19: New Latin, from _platina , on the model of other metals with the suffix -um

Example Sentences

Prices have soared 99% this year, outpacing both gold and platinum.

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Any coin issued under the laws of any state or any gold, silver, platinum or palladium bullion of a certain fineness, if a trustee keeps physical possession of it, are not included.

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Their findings, published in the open-access journal ACS Central Science, clarify why precious metals such as gold, silver and platinum excel in catalytic processes.

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Mapplethorpe genuflects at the altar of that icon with a platinum portrait of Warhol, backed by a halo of light and surrounded by silk panels that form a cross.

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The advance in prices was led by a notable increase in non-ferrous metal products, driven by sharp increases in prices for unwrought gold, platinum group metals and silver and their metal alloys, Statistics Canada said.

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Related Words

• gold 
• iron 
• metal 
• mineral