Extremely Large Rutilated Quartz Cabochon - Brazil

An exceedling large desktop or cabinet specimen, this oval cabochon of rather transparent rock crystal quartz contains needle-like inclusions of rutile. Rutile is the natural mineral form of titanium dioxide. It is generally dark red or metallic black its name rutile coming from the Latin for “dark red”. It forms prismatic crystals that can be thin as hairs, as in this specimen of rutilated quartz. Rutile forms twins and sprays of six or eight crystals frequently intersecting. The cabochon bears a "natural" on one side, evidence of the original crystal surface.
Weighing approximately 6537.50 carats. Measuring 5 ¼ x 3 ¾ x 2 ½in  -  Sold for $3,250 plus Premium and tax

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Bonhams. Natural History, 30 Apr 2008. New York