Calcite on Prehnite Crystal Cluster | Double Terminated Calcite | 77 grams | Mumbai, India | SO24 Morganite 5 on the Mohs scale

5 on the Mohs scale of hardness

It often forms as prismatic crystals with a square or rectangular cross-section

Approx Weight (per piece): 7

Since it forms easily from saline water

Calcite on Prehnite Crystal Cluster | Double Terminated Calcite | 77 grams | Mumbai, India | SO24 Morganite 5 on the Mohs scaleCalcite is found throughout the world in sedimentary, metamorphic, and igneous rocks. Some geologists consider it to be a "ubiquitous mineral" one that is found everywhere. Calcite is the principal constituent of limestone and marble. On this particular specimen there are 2 double terminated calcite points. Penhnite can form prismatic, tabular, or pyramidal crystals, but usually occurs in botryoidal, reniform, stalactitic, granular, or compact habits.