Green Calcite

Hardness: 3 on the Mohs scale. Color: Pale green to olive green, sometimes with white banding. Luster: Vitreous to resinous. Crystal Structure: Trigonal. Cleavage: Perfect rhombohedral cleavage, meaning it breaks into distinctive parallelogram shapes along three directions. Specific Gravity: 2.71.

Calcite is a common mineral found in various geological settings. Green calcite often forms in hydrothermal veins, hot springs, and caves, where calcium-rich waters deposit the mineral. The green color is typically due to inclusions of other minerals, such as chlorite, or trace elements like iron. It can be found in sedimentary, metamorphic, and igneous rocks.

While not as hard as many gemstones, green calcite is popular in the lapidary arts for carving ornamental objects, spheres, and tumbled stones. It is also highly valued by mineral collectors for its aesthetic appeal and crystal formations. In a broader sense, calcite is used extensively in construction (as limestone and marble), agriculture, optics, and as a raw material for cement.

Calcite is one of the most common and widespread minerals on Earth, making up a significant portion of the Earth's crust. It is the primary mineral in limestone and marble. Green calcite is often associated with emotional healing and balancing properties in metaphysical practices. Its perfect rhombohedral cleavage is a key diagnostic property, allowing it to easily break into distinct, angled fragments.

Green calcite can be identified in the field by its relatively low hardness (easily scratched with a copper coin), perfect rhombohedral cleavage, and reaction to acid (it will effervesce vigorously when a drop of dilute hydrochloric acid is applied). Its color can range from very pale to deep green. Common locations include Mexico, Peru, Brazil, and various regions in the United States. Collectors often seek out well-formed crystals and pieces with vibrant coloration for display.