igneous
Basalt
Extrusive Igneous Rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, typically dark gray to black in color with an aphanitic or fine-grained texture and dull luster.
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Physical properties
Hardness of 6 on the Mohs scale, typically dark gray to black in color with an aphanitic or fine-grained texture and dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity lava rich in iron and magnesium exposed at or very near the surface of a planet or moon.
Uses & applications
Widely used in construction as crushed stone for road bases, concrete aggregate, and in the manufacturing of rock wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crustal portions underlying the ocean basins and also forms massive structures like the Giant's Causeway.
Field identification & locations
Identify by its dark, fine-grained appearance and dense, heavy weight; commonly found in volcanic regions worldwide.
