metamorphic
Crystalline limestone (marble-like calcite rock)
Calcite, CaCO₃; likely recrystallized limestone (marble)
AI-generated identification · may be incorrectWhite to gray, coarse crystalline texture with vitreous to pearly luster; calcite has Mohs hardness 3, perfect rhombohedral cleavage, and specific gravity about 2.71. The specimen appears granular and weakly foliated, though image resolution limits certainty.
Identified More metamorphic →
Explore Crystalline limestone (marble-like calcite rock) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
White to gray, coarse crystalline texture with vitreous to pearly luster; calcite has Mohs hardness 3, perfect rhombohedral cleavage, and specific gravity about 2.71. The specimen appears granular and weakly foliated, though image resolution limits certainty.
Formation & geological history
Forms when limestone recrystallizes during low- to medium-grade metamorphism, commonly near intrusions or within mountain belts. Its age depends on the original limestone and may range from Paleozoic to younger.
Uses & applications
Used as dimension stone, aggregate, cement and lime feedstock; attractive marble is used for sculpture, countertops, and architectural facing. This small fragment has negligible commercial value.
Geological facts
Calcite effervesces vigorously in dilute hydrochloric acid or household vinegar, especially when powdered or freshly scratched. Marble is composed mainly of interlocking calcite crystals and may preserve faint fossils or bedding from its limestone precursor.
Field identification & locations
Common in metamorphic belts and quarry waste; distinguish it from quartz by its softness, cleavage, and acid reaction. Likely locations include marble districts worldwide, such as Italy, Vermont, Greece, and Colorado.
More like this
