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A polished Cold Mountain Thunderegg specimen pair featuring sandy colored jasper with red, browns, and blue-gray patterning in the center, with a chalky bumpy exterior.
Polished faces: 9.6cm x 6.4cm and 9.6cm x 6.3cm
Approx. 1" & 1.5" deep
15.4oz 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.