A giant cube deposit of purple fluorite achieved $125,000 to lead Heritage Auctions' Nature and Science signature sale in Dallas on October 19.
Measuring 10.5 x 9.75 x 6 inches, and featuring accents of barelite, spharelite and calcite, the huge deposit was discovered in the Elmwood Mine in Carthage, Tennessee.
A spray of legrandite achieved an impressive figure of $93,750. It was found in the Ojuela Mine, Mexico and features bright golden blades extending from a matrix of reddish limonite.
Only two locations in the world are known to produce legrandite to this scale. It is extremely rare for the mineral to form into anything other than microscopic crystals.
A spray of blue, pink and green tourmaline - discovered in 1997 in the Sapo Mine, Brazil - made $81,250.
The formation is referred to as a "shaving brush", and is the second largest of a number discovered in a pocket deep within the mine.
A large sulphur formation, discovered in the Agrigento province in Sicily, was another highlight of the sale, achieving $68,750.
Comprising an enormous dipyramidil yellow crystal formed around a block of calcite or argonite, the highly transparent deposit contains samples of bitumen which can be easily viewed under and within the crystal.
A previous auction of rare minerals from the same collection in June of this year made $4m and featured the sale of a chunk of extremely rare rose quartz for $662,500.
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