igneous
Basalt
Extrusive Igneous Rock
AI-generated identification · may be incorrectHardness of 6 on Mohs scale, dark gray to black color, dull luster, fine-grained aphanitic crystal structure, high density specific gravity around 2.9.
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Physical properties
Hardness of 6 on Mohs scale, dark gray to black color, dull luster, fine-grained aphanitic crystal structure, high density specific gravity around 2.9.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava exposed at or very near the Earth's surface.
Uses & applications
Widely used in construction as crushed stone for road bases, concrete aggregate, and dimension stone.
Geological facts
Basalt is the most common rock type in the Earth's crust underlying the world's ocean basins and forming massive volcanic provinces like the Deccan Traps.
Field identification & locations
Identify in the field by its dark, fine-grained matrix, often containing small visible crystals of plagioclase or olivine; commonly found globally in volcanic regions.
