tantalum

American  

[tan-tl-uhm] / ˈtæn tl əm /

noun

Chemistry.

1. a gray, hard, rare, metallic element occurring in columbite and tantalite and usually associated with niobium: used, because of its resistance to corrosion by most acids, for chemical, dental, and surgical instruments and apparatus. Ta; 180.948; 73; 16.6.

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tantalum British  

/ ˈtæntələm /

noun

1. a hard greyish-white metallic element that occurs with niobium in tantalite and columbite: used in electrical capacitors in most circuit boards and in alloys to increase hardness and chemical resistance, esp in surgical instruments. Symbol: Ta; atomic no: 73; atomic wt: 180.9479; valency: 2, 3, 4, or 5; relative density: 16.654; melting pt: 3020°C; boiling pt: 5458±100°C

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tantalum Scientific  

/ tăn′tə-ləm /

1. A hard, heavy, gray metallic element that is highly resistant to corrosion at low temperatures. It is used to make light-bulb filaments, surgical instruments, and glass for camera lenses. Atomic number 73; atomic weight 180.948; melting point 3,017°C; boiling point 5,458°C; specific gravity 16.6; valence 2, 3, 4, 5.

2. See Periodic Table

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Etymology

Origin of tantalum

1795–1805; < New Latin; named after Tantalus

Example Sentences

In addition to lithium, Somaliland is rich in tantalum and niobium -- critical minerals for electronics -- as well as gold, copper, and emeralds, according to the ministry, though quantities have yet to be verified.

From Barron's • Feb. 25, 2026

The company also said it continues to strengthen industrywide supply-chain due diligence, and last year told suppliers to stop obtaining tin, tungsten, tantalum and gold from Congo and neighboring Rwanda.

From The Wall Street Journal • Dec. 8, 2025

Bahrami noted that tantalum stands out because it is extremely durable and can withstand the harsh cleaning used to remove contamination during fabrication.

From Science Daily • Nov. 17, 2025

Last year Rwandan mining company Trinity Metals secured a $3.9m grant from the DFC to help develop the three mines that it owns in the country, producing tin, tantalum and tungsten.

From BBC • Nov. 9, 2025

Certain compounds of tin-oxides, particularly if they contain tantalum, are by fusion with carbonate of soda reduced with difficulty; but by the addition of some borax, the reduction to the metallic state is easily effected.

From A System of Instruction in the Practical Use of the Blowpipe Being A Graduated Course Of Analysis For The Use Of Students And All Those Engaged In The Examination Of Metallic Combinations by Anonymous