Bubbles in Volcanic Rock  is a large Purple Geode Druzy slice with Purple Dragon Vein Agates on a large Sterling Silver Chain. Across the Geode you have faceted briolette Citrines and small 4mm faceted amethyst beads. It is approximately 18" long and the large Geode is 3" across with Matching Earrings.
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Geodes begin as bubbles in volcanic rock or as animal burrows, tree roots or mud balls in sedimentary rock. Over time, the outer shell of the spherical shape hardens, and water containing silica precipitation forms on the inside walls of the hollow cavity within the geode. The silica precipitation can contain any variety of dissolved minerals.

Over a period of thousands of years, layers of silica cool, forming crystals of different minerals within the cavity. Different types of silica cool at varying temperatures, thus creating layers of different types of mineral crystals. Each is unique!