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A polished Cold Mountain Thunderegg specimen pair featuring streaked jasper in sandy to reddish brown shades with brecciation filled with translucent chalcedony. Each half of the pair has a full back, with different depths.
Polished faces: 7.5cm x 5.5cm and 7.4cm x 6cm
Approx. 1" & 1.5" deep
12.5oz together
Cold Mountain Thundereggs are from the Sierra Mountains in Mexico. The thundereggs can contain water banding and feature red, mauve, or black “webbing.” While technically a rhyolite due to its thunderegg nature, Cold Mountain Thundereggs are highly silicate and feature large amounts of brecciation that has also been filled with silica, so this material takes an exceptional polish, making it ideal for both cabochons and specimens.