What's tungsten?
(REL)
Routes of Exposure: Inhalation; Ingestion; Skin and/or eye contact
Target Organs: Eyes, skin, respiratory system, blood
Levels In Humans:
Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
- Blood/mg dm-3: 0.001
- Bone/p.p.m: 0.00025
- Liver/p.p.m: n/a
- Muscle/p.p.m: n/a
- Daily Dietary Intake: 0.001-0.015 mg
- Total Mass In Avg. 70kg human: 0.02 mg
Who / Where / When / How
- Discoverer: Fausto and Juan José de Elhuijar
- Discovery Location: Vergara Spain
- Discovery Year: 1783
- Name Origin:
- Swedish: tung sten (heavy stone): W symbol from its German name wolfram which is named after wolframite.
- Abundance of Tungsten:
- Earth's Crust/p.p.m.: 160.6
- Seawater/p.p.m.: 0.000092
- Atmosphere/p.p.m.: 411
- Sun (Relative to H=1E12): 0.28
- Sources of Tungsten:
- Occurs in the minerals scheelite (CaWO4) and wolframite [(Fe,Mn)WO4]. Annual world wide production is around 45,100 tons. Primary mining areas are China, Malaysia, Burma, bolivia, canada, Australia, Japan and USA.
- Uses of Tungsten:
- Used widely in the electronics industry. Made into filaments for vacuum tubes and electric lights. Also used in contact points in cars, welding electrodes, rocket nozzles and cutting tools. Combined with calcium or magnesium it makes phosphors.
- Additional Notes:
- Some sources give the German chemist Karl Wilhelm Scheele as the first to isolate the metal in 1880, but most sources credit the Elhuijar brothers.
COLLETED BY HANNS FROM WWW.CHINATUNGSTEN.COM
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