platinum

American  

[plat-n-uhm, plat-nuhm] / ˈplæt n əm, ˈplæt nəm /

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.

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adjective

1. made of platinum.

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

platinum British  

/ 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

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platinum Scientific  

/ plăt′n-əm /

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

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Etymology

Origin of platinum

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

Example Sentences

“Gold, silver and platinum have all started the year strongly, reflecting a mix of geopolitical hedging, financial flows and structural investment themes,” the head of Commodity Strategy adds.

From The Wall Street Journal

It is also a major producer of gold, silver, emeralds, platinum and coal.

From BBC

The platinum refiner stands out from its European chemical peers struggling with oversupply dynamics as the market for platinum group metals remains tight, the analysts say.

From The Wall Street Journal

Venezuela's neighbour to the west, Colombia is home to substantial oil reserves and is a major producer of gold, silver, emeralds, platinum and coal.

From BBC

These include elevated levels of rare elements commonly associated with comets, such as platinum and iridium.

From Science Daily

Related Words

• gold
• iron
• metal
• mineral