4.79" Sparkling Cave Calcite (Aragonite) Specimen - Potosi Mine, Mexico (#706)

This is an absolutely stunning 4.79" long cluster of sparkling aragonite crystals from the famous Potosi Mine in the Santa Eulalia Mining District of Chihuahua, Mexico.

Although it is often referred to as "cave calcite" it is actually a formation of aragonite crystals. Calcite and aragonite are both carbonates with the same chemical formula (CaCO3), but they have different crystal structures and symmetries.

Cave calcite forms underground due to groundwater deposition. While it often forms stalactites and stalagmites it can also form unique, branching, tree-like structures known as floss ferri (flowers of iron) or frostwork.