1. 1.60" / 40mm
2. 1.55" / 39mm
3. 1.61" / 40mm
4. 1.61" / 41mm
5. 1.63" / 41mm
Calcite is a calcium carbonate mineral with a hardness of 3. Calcites are among the most varied and abundant crystals, and they occur in a wide variety of forms and colors. The molecular structure of the crystals is rhombohedral, but specimens can appear as scalenohedrons, rhombohedrons, prisms, masses, stalactites, etc. Calcite makes up a major part of most marbles and limestones. Calcite crystals are found on every continent. Large deposits of brightly colored Calcites occur in Mexico, and some of the most desired forms, such as Stellar Beam Calcites, are found in the USA.