Interesting Facts About Tungsten

Distribution of Tungsten Resources

Global tungsten resource reserves are abundant. The tungsten content in the Earth’s crust is approximately 0.001%. More than 20 types of tungsten minerals have been identified. These include tungsten ore, wolframite, scheelite, and wolframite ore. Only wolframite and scheelite are economically viable. Wolframite accounts for around 30% of the total resources, while scheelite makes up about 70%.

Regional Distribution

Worldwide tungsten occurrences concentrate chiefly in the Alpine-Himalayan region and along the Pacific geological belt.
In Russia, tungsten ore occurrences are located in the Northern Caucasus, Eastern Siberia, and the Far East of the Zinn-Holt-A-Lin range; the largest mine is Verkhne-Kayrakty.
In the United States, tungsten mines are concentrated in California and Colorado.
In Canada, tungsten deposits are mainly situated in the Selwyn ore belt.

Country Distribution

According to the United States Geological Survey (2015), global tungsten reserves amount to approximately 3 300 000 tonnes. China holds 1 900 000 tonnes of these resources, representing around 58% of the global total.

Classification of Tungsten Ore

Wolframite

Owing to the varying proportions of iron wolframite and manganese wolframite, it is also referred to as tungsten-manganese iron ore. This type accounts for approximately 30% of global tungsten ore resources. A higher iron content results in an increased tungsten concentration. The colour of wolframite varies with the iron and manganese content. Common colours include grey, dark reddish-brown, light brown, dark brown, and brown. Wolframite exhibits a metallic or semi-metallic lustre. It is brittle and shows weak magnetic properties. It is primarily used for refinement and the production of tungsten.

Scheelite

Scheelite is a granular or massive mineral that is transparent to translucent. Its colour varies with the molybdenum content. Common colours include white, grey, yellow, violet, brown, pink, and green. Scheelite constitutes approximately 70% of global tungsten resources. The mineral exhibits luminescence, displaying light blue and yellow fluorescence under UV irradiation.
Scheelite forms in contact metasomatic deposits, high-temperature hydrothermal veins, and greisens. It is primarily used in the production of ferrotungsten and may also be used for permanent magnets.