Black Marble
Recrystallized Limestone (CaCO3)
Rock Type: metamorphic

Physical Properties
Hardness: 3 on Mohs scale; Color: Black with white/grey veins; Luster: Polished/Vitreous; Structure: Granular/Crystalline; Cleavage: Perfect rhombohedral in calcite crystals; Specific Gravity: 2.7-2.8
Formation & Geological History
Formed through the regional metamorphism of organic-rich limestone or dolostone. High pressure and heat cause the calcite to recrystallize into an interlocking mosaic, while carbon or bitumen creates the black coloration.
Uses & Applications
Commonly used for interior decoration, tumbled stones for meditation, architectural tiles, sculpture, and as architectural accents in high-end construction.
Geological Facts
The white veins are typically calcite pulses that filled fractures in the rock after the initial formation. Black marble is often featured in historic mausoleums and luxury lobbies for its dramatic contrast.
Field Identification & Locations
Identify in the field by its softness (can be scratched with a penny or steel blade) and its effervescence when exposed to diluted hydrochloric acid. Common in regions like Spain (Nero Marquina) and Greece.
Identified on: 5/13/2026
Mode: Standard