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Amethyst Quartz Geode

Amethyst Quartz GeodeAmethyst Quartz Geode

TMM2415-1
SiO2
Found in Rio Grande do Sul, Brazil

This enormous amethyst geode weighs about 250 pounds. A geode is a hollow globular rock that is lined with inward-facing crystals. Geodes form over time as water seeps into cavities within rocks and leaves behind different minerals. These minerals can form large, distinct crystals as seen in this amethyst quartz geode. Can you spot another mineral, white calcite, inside this geode?

This wonderful specimen has a rich purple amethyst color. Amethysts are the most valuable variety of quartz, and were one of the first gemstones used by people around the world. The Greeks believed that drinking wine from an amethyst cup would prevent intoxication. Royalty has also favored the purple gemstone, and at one time amethysts were reserved for royalty alone. Amethysts are found in the British Crown jewels.