igneous
Basalt
Extrusive Igneous Rock
AI-generated identification · may be incorrectHardness 6 on Mohs scale, dark gray to black color, aphanitic to porphyritic texture, dull luster, specific gravity around 2.9.
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Physical properties
Hardness 6 on Mohs scale, dark gray to black color, aphanitic to porphyritic texture, dull luster, specific gravity around 2.9.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava exposed at or very near the Earth's surface.
Uses & applications
Used extensively in construction as crushed stone for road bases, aggregate in concrete, and manufacturing rock wool.
Geological facts
Basalt is the most common rock type in the Earth's crustal portions underlying the ocean basins and forms massive features like the Columbia River Flood Basalts.
Field identification & locations
Identify by its dark, fine-grained matrix and heavy weight; commonly found in volcanic regions worldwide.
