Quartz - , USA - geode is about 18 cm with a very thick rind
Mineral: Quartz
Locality: Monroe County, Indiana, USA
Dimensions: geode is about 18 cm with a very thick rind

Description: quartz and microcrystalline quartz at least 4 generations of crystalline and microcrystalline quartz with the cavity lined by smoky quartz. This example weighs nearly 18 lbs.