Rock Identifier
Pale green translucent mineral fragment, likely calcite (Calcite (CaCO₃), tentatively; possibly green fluorite or prehnite) — mineral
mineral

Pale green translucent mineral fragment, likely calcite

Calcite (CaCO₃), tentatively; possibly green fluorite or prehnite

AI-generated identification · may be incorrect

Light green, translucent, vitreous-to-pearly luster with apparent cleavage and uneven fracture; calcite has Mohs hardness 3 and rhombohedral cleavage, while fluorite is harder (4) with cubic cleavage. Specific gravity is approximately 2.7 for calcite or 3.2 for fluorite.

Identified More mineral →
Explore Pale green translucent mineral fragment, likely calcite in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

Physical properties

Light green, translucent, vitreous-to-pearly luster with apparent cleavage and uneven fracture; calcite has Mohs hardness 3 and rhombohedral cleavage, while fluorite is harder (4) with cubic cleavage. Specific gravity is approximately 2.7 for calcite or 3.2 for fluorite.

Formation & geological history

Likely formed in hydrothermal veins or cavities; calcite is common in sedimentary and metamorphic settings and ranges from ancient to recent geological ages. The image alone cannot establish a precise age or identity.

Uses & applications

Calcite is used in cement, lime, aggregate, optical devices, and collections; green fluorite and prehnite are mainly collector or ornamental minerals. This small fragment has modest commercial value.

Geological facts

A vinegar test causes visible fizzing in calcite, especially when powdered; fluorite does not fizz. A steel nail can scratch calcite but generally not fluorite or prehnite.

Field identification & locations

Common localities include Mexico, the United States, China, and Europe for calcite; fluorite is widespread in hydrothermal veins. Confirm with hardness, cleavage, streak, specific gravity, and acid testing rather than color alone.