7.7" Hedenbergite Included Quartz Crystal Cluster - Mongolia

This is an attractive cluster of green quartz crystals that was collected from the Huanggang Mines of Inner Mongolia. The green color of the crystals can be attributed to hedenbergite inclusions within the quartz. These needle-like inclusions become apparent when looking at the crystal's terminations and/or backlighting the crystals.

Silicon Dioxide, also known as SiO2 or Quartz, is the second most abundant mineral in the Earth's crust. Quartz crystals generally grow in silica-rich, hot watery solutions called hydrothermal environments, at temperatures between 100°C and 450°C, and usually under very high pressure. Quartz veins are formed when open fissures are filled with hot water during the closing stages of mountains forming, and can be hundreds of millions of years old.

Hedenbergite is a calcium iron (magnesium) silicate that often bears a range of green to brown coloration. The crystals are typically opaque and occur in stubby or prismatic aggregates. Inner Mongolia, Russia and Greece all produce quartz crystals that are green in color as a result of fibrous hedenbergite inclusions. A variety of hedenbergite crystal forms can be found in Sweden as well, with dark-green blocky crystals coming from the Nordmark Odal Field.

Hedenbergite was given its name in 1819 by Jöns Jakob Berzelius, a chemist in Sweden. He named the mineral in honor of Anders Ludvig Hedenberg, a chemistry student and co-worker of Berzelius. Hedenberg is credited with the first documented discovery and description of Hedenbergite in Tunaberg, Sweden.

The general chemical formula of Hedenbergite is CaFe2+Si2O6 .
Quartz var. Prase (Hedenbergite inclusions)
Huanggang Mines, Chifeng, Inner Mongolia
7.7 x 4.9 x 3"