Scheelite

Its crystals are in the tetragonal crystal system, appearing as dipyramidal pseudo-octahedra. Colors include golden yellow, brownish green to dark brown, pinkish to reddish gray, orange and colorless. Transparency ranges from translucent to transparent and crystal faces are highly lustrous (vitreous to adamantine). Scheelite possesses distinct cleavage and its fracture may be subconchoidal to uneven. Its specific gravity is high at 5.9–6.1 and its hardness is low at 4.5–5. Aside from pseudo-octahedra, scheelite may be columnar, granular, tabular or massive in habit. Druzes are quite rare and occur almost exclusively at Zinnwald, Czech Republic. Twinning is also commonly observed and crystal faces may be striated. Scheelite streaks white and is brittle. Gems cut from transparent material are fragile. Scheelite's refractive index (1.918–1.937 uniaxial positive, with a maximum birefringence of 0.016) and dispersion (0.026) are both moderately high. These factors combine to result in scheelite's high lustre and perceptible "fire", approaching that of diamond. Scheelite fluoresces under shortwave ultraviolet light, the mineral glows a bright sky-blue. The presence of molybdenum trace impurities occasionally results in a green glow. Fluorescence of scheelite, sometimes associated with native gold, is used by geologists in the search for gold deposits.

Scheelite occurs in contact metamorphic skarns; in high-temperature hydrothermal veins and greisen; less commonly in granite pegmatites. Temperature and pressure of formation is between 200 and 500 °C and from 200 to 1,500 bars. Typical mineral association includes cassiterite, wolframite, topaz, fluorite, apatite, tourmaline, quartz, grossular–andradite, diopside, vesuvianite and tremolite. Scheelite usually occurs in tin-bearing veins; and is sometimes found in association with gold. Fine crystals have been obtained from Caldbeck Fells in Cumbria, Zinnwald/Cínovec and Elbogen in Bohemia, Guttannen in Switzerland, the Riesengebirge in Silesia, Dragoon Mountains in Arizona and elsewhere. At Trumbull in Connecticut and Kimpu-san in Japan large crystals of scheelite completely altered to wolframite have been found: those from Japan have been called “reinite.” It was mined until 1990 at King Island, Australia, Glenorchy in Central Otago and Macraes Flat in North Otago and also at The Golden Bar mine at Dead Horse Creek during World War 1 in Nelson, New Zealand. There is a high concentration of Scheelite in Northeast of Brazil, mainly in the Currais Novos mine in Rio Grande do Norte State.

Scheelite is an essential source of tungsten, which is an important metal for the metal-working, mining, and petroleum industries. This mineral is also highly valued among collectors for its fluorescence. Scheelite is a gorgeous gemstone if cut properly, but it is rare to find specimens that are high quality enough for this application.

Scheelite was first described in 1751 for an occurrence in Mount Bispbergs klack, Säter, Dalarna, Sweden, and named for Carl Wilhelm Scheele (1742–1786). Owing to its unusual heaviness, it had been given the name tungsten by the Swedes, meaning “heavy stone.” The name was later used to describe the metal, while the ore itself was given the name scheelerz or scheelite.

Scheelite was first described in 1751 for an occurrence in Mount Bispbergs klack, Säter, Dalarna, Sweden, and named for Carl Wilhelm Scheele (1742–1786). Owing to its unusual heaviness, it had been given the name tungsten by the Swedes, meaning “heavy stone.” The name was later used to describe the metal, while the ore itself was given the name scheelerz or scheelite.

Scheelite transforms negative energy into positive energy. It balances the Sacral, Solar Plexus, and Crown chakras to allow for creativity, while enhancing clarity and organizational skills. It can assist in goal achievement by improving focus and commitment. Many find it helpful to meditate with it daily or keep a piece with them for best results.