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CMT151 Cold Mountain Thunderegg Specimen


This polished specimen displays dusty pink with hints of yellow and gray-blue, and a small chalcedony-filled vugg that goes through to the back of the specimen. This piece does have a crack that has been treated.

5.25" x 3.25" x 1.5"
14.3 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.