Technical Fact Sheet – Tungsten - US EPA

Tungsten is a naturally occurring element that exists in the form of minerals, but typically not as a pure metal (ATSDR 2005). The color of tungsten may range from white for the pure metal to steel - gray for the metal with impurities (NIOSH 2016). There are more than 20 known tungsten-bearing minerals (ATSDR 2005). ................
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