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A polished Cold Mountain Thunderegg specimen pair featuring muted tan to golden yellow brecciated jasper, with hints of pink and blue-gray, and a large fracture filled with chalcedony.
Polished faces: 12cm x 8.5cm and 12cm x 8cm
Approx. 1.75" deep
2lb 6.4oz 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.