igneous
Basalt
Extrusive Igneous Rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, typically dark gray to black, aphanitic texture with a dull to sub-with luster, and composed mainly of plagioclase feldspar and pyroxene.
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Physical properties
Hardness of 6 on the Mohs scale, typically dark gray to black, aphanitic texture with a dull to sub-with luster, and composed mainly of plagioclase feldspar and pyroxene.
Formation & geological history
Formed from the rapid cooling of low-viscosity, magnesium- and iron-rich lava exposed at or very near the surface of a planet or moon.
Uses & applications
Used extensively in construction as crushed aggregate, railroad ballast, and in the production of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's oceanic crust and also makes up extensive volcanic formations on the Moon and Mars.
Field identification & locations
Identify in the field by its fine-grained, dark-colored matrix, heavy weight, and occasional vesicular texture from trapped gas bubbles. Found globally in volcanic provinces.
