igneous
Basalt
Mafic extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, typically dark black or grey in color with a fine-grained, aphanitic texture.
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Physical properties
Hardness of 6 on the Mohs scale, typically dark black or grey in color with a fine-grained, aphanitic texture.
Formation & geological history
Formed from the rapid cooling of low-viscosity, magnesium- and iron-rich lava exposed at or very near the Earth's surface.
Uses & applications
Widely used in construction as crushed aggregate, railroad ballast, and dimension stone for building facades.
Geological facts
Basalt is the most common rock type in the Earth's crust, primarily making up the ocean floors and massive volcanic provinces.
Field identification & locations
Identified by its dark color and fine-grained matrix, often found in volcanic regions and oceanic islands worldwide.
