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CMT150 Cold Mountain Thunderegg Specimen


This polished specimen displays dusty pink with hints of yellow and gray-blue, and a small vugg with partial chalcedony growth.

6.5" x 4.25" x 1.75"
2 lb 3.1 oz

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.