igneous
Basalt
Mafic extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on Mohs scale, dark gray to black color, aphanitic texture with dull to sub-metamorphic luster, composed primarily of plagioclase and pyroxene.
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Physical properties
Hardness of 6 on Mohs scale, dark gray to black color, aphanitic texture with dull to sub-metamorphic luster, composed primarily of plagioclase and pyroxene.
Formation & geological history
Formed by the rapid cooling of low-viscosity lava flows rich in iron and magnesium at the Earth's surface, often associated with volcanic hotspots and oceanic ridges.
Uses & applications
Used extensively in construction as crushed stone for road bases, concrete aggregate, and in the production of rock wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crust, underlying most ocean basins, and is also found in vast lava plateaus on land as well as on the Moon and Mars.
Field identification & locations
Identify by its dark, fine-grained matrix and heavy density. Commonly found globally in volcanic regions and ancient lava flows.
