Picture of the Day: The Cave of Crystal Giants
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980 ft (300 m) beneath the surface of Naica, Chihuahua, Mexico is a mine filled with giant gypsum crystals.
980 ft (300 m) beneath the surface of Naica, Chihuahua, Mexico is a mine filled with giant gypsum crystals.
In this amazing close-up we see a beautiful opal from Yoawh, Queensland, Australia. The length of this polished opal is a mere 20 mm but its features are gorgeous. The opal is a part of the Willems Miner Collection.
Seen here is a 773 gram polished Chinga meteorite. The quarter-cut specimen was found in Turvinskaya, Russia and has been cut and polished on two sides. The rest of the meteorite retains its natural light brown crust, creating a dramatic contrast. This particular specimen, which was offered by Arizona Skies Meteorites has been sold,…
Photograph via THE ARKENSTONE/IROCKS.COM Rob Lavinsky of The Arkenstone (www.irocks.com) brought this fascinating mineral to market, selling it to a buyer for $5,000. The specimen, which Lavinsky describes as Chalcedony on Chrysocolla stalactites (pocket), measures 9 x 7 x 6 cm. It was originally obtained by Frank Valenzuela back in the 1960s from the…
SUNSET FIRE OPAL Photograph by Jeff Schultz | gemstoneJEFF on Flickr In this beautiful close up by gemstone hobbyist Jeff Schultz, we see a stunning Mexican fire opal. When illuminated just right, it looks like a sunset above the clouds. According to Wikipedia, fire opals are transparent to translucent opals with warm…
Opal is a hydrated amorphous form of silica. Its water content may range from 3% to 21% by weight, but is usually between 6% to 10%. Because of its amorphous character it is classed as a mineraloid, unlike the other crystalline forms of silica which are classed as minerals. It is deposited at a…
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