Tungsten is an elemental metal with the chemical symbol W. It is found in several compounds and is mined in underground and open pit mines all over the world. China is the top ore producer, with over half of the world’s supply. The primary types of tungsten ores and concentrates are wolframite and scheelite.
Encyclopedia Britannica indicates that Wolframite ((Fe,Mn)WO4) “is commonly associated with tin ore in and around granite.” Wolframite ore with very high iron concentrations is ferberite. Those with very high manganese concentrations are hubnerite (heubnerite). As seen in the photo below wolframite is black or brown in color.
Scheelite (CaWO4) is a calcium based tungsten ore. Britannica notes that it “commonly occurs as compact or granular masses in contact metasomatic deposits, high temperature veins, and granite pegmatites.” It is white or brown as seen in the photo below.
The ore is concentrated at the mine site until it reaches 65% tungsten oxide (WO3) content. Tungsten has a high density so gravity methods separate it from the waste rock. After crushing the ore it passes over shaker tables with water and the lower density materials are the tailings. Magnetic separators can further increase concentrations in some ore bodies. Float cells can also improve the quality by using chemicals.
Buffalo Tungsten purchases tungsten ores and concentrates. We send them to our joint venture company Niagara Refining for processing. They chemically treat the material to remove impurities to make the intermediates APT, BTO and YTO. We reduce these materials into pure tungsten powder and tungsten carbide powder.
As a leading tungsten powder producer we always have a need for more raw materials. If you have a supply of tungsten concentrates please contact us. Send us an assay of your ore to evaluate. We can analyze a sample in our lab to compare results. If we feel the material will meet our needs we would be happy to discuss an offtake agreement to purchase your materials.