mineral
Likely calcite fragment
Calcite (calcium carbonate, CaCO₃)
AI-generated identification · may be incorrectPale cream to honey-colored, translucent, with a vitreous to pearly luster and prominent rhombohedral cleavage; Mohs hardness 3, specific gravity about 2.71. The rough surface and lighting limit certainty; it may also be a pale feldspar or quartz fragment.
Identified More mineral →
Explore Likely calcite fragment in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Pale cream to honey-colored, translucent, with a vitreous to pearly luster and prominent rhombohedral cleavage; Mohs hardness 3, specific gravity about 2.71. The rough surface and lighting limit certainty; it may also be a pale feldspar or quartz fragment.
Formation & geological history
Calcite commonly forms in sedimentary limestones, hydrothermal veins, cavities, and metamorphic marbles, precipitating from calcium-rich fluids over a wide range of geological ages. A dilute acid test should produce vigorous effervescence if it is calcite.
Uses & applications
Used in cement, lime, agricultural soil treatment, fillers, and optical/cal收藏lecting specimens; this small rough piece has little commercial value.
Geological facts
Calcite is highly variable in crystal habit and commonly fluoresces under ultraviolet light. Its rhombohedral cleavage and acid reaction distinguish it from quartz.
Field identification & locations
Look for cleavage surfaces meeting at non-90° angles and test carefully with vinegar or dilute hydrochloric acid; avoid damaging valuable specimens. Common worldwide, especially in limestone regions and hydrothermal deposits.
