Marble

Physical Properties

Hardness: 3 on Mohs scale; Color: typically white, pinkish-white, or gray; Luster: sugary or vitreous; Crystal structure: Trigonal/Hexagonal; Cleavage: rhombohedral (in individual grains); Specific Gravity: 2.7

Formation & Geological History

Formed from regional or contact metamorphism of limestone or dolostone. High heat and pressure cause the original carbonate mineral grains to recrystallize into a dense network of interlocking crystals.

Uses & Applications

Extensively used in construction, sculpture, flooring, and as a source for calcium carbonate in agricultural or industrial applications.

Geological Facts

Marble has been the primary medium for artists like Michelangelo. Unlike limestone, marble lacks fossils because the intense heat and pressure of metamorphism usually destroy them during recrystallization.

Field Identification & Locations

Identify in the field by its characteristic 'sugary' crystalline texture and its reaction to dilute hydrochloric acid (it will fizz). It can be scratched with a steel nail but not easily by a fingernail.

Identified on: 4/14/2026

Mode: Standard