Calcite group from Indonesia

A calcite group from Indonesia. The crystals in this group display typical elongated columnar geometry, a growth variant that occurs under specific flow conditions in karst caves.

Columnar growth in calcite is a function of the solution flow direction: strong directional currents produce elongated crystals in the direction of flow, while stagnant solutions produce more blocky or scalenohedral crystals.

The elongated Indonesian calcites document cave areas with active water currents during the mineralization phase. Such pieces are palaeohydrologically interesting and document the hydrogeological history of the deposit.

Mohs 3 requires careful handling; scratches from harder materials should be avoided.

An Indonesian collector's piece with columnar growth geometry and palaeohydrologically documented karst provenance.