igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, dark gray to black color, aphanitic to porphyritic texture, and dull to sub-vitreous luster.
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Physical properties
Hardness of 6 on the Mohs scale, dark gray to black color, aphanitic to porphyritic texture, and dull to sub-vitreous luster.
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 for crushed stone, aggregate in concrete, road base, and manufacturing of rock wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's oceanic crust and also forms extensive volcanic provinces like the Columbia River Flood Basalts.
Field identification & locations
Identify by its dark color, fine-grained matrix, and dense, heavy feel. Found globally in volcanic regions and ocean floors.
