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A polished Cold Mountain Thunderegg specimen featuring a mix of translucent chalcedony and brecciated jasper, in muted shades of pink with brick red, brown, and blue-grey detailing.
Polished face: 8cm x 6.2cm
Approx. 1" deep
3.8oz
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.