is a common extrusive volcanic rock (That means it's lava). It is usually grey to black and fine-grained due to its rapid cooling. It may be “porphyritic” containing larger crystals in a fine matrix, or “vesicular”, having bubbles from gases. According to the official definition, basalt is an igneous rock that contains, by volume, less than 20% quartz and less than 10% feldspar

On Earth, most basalt magmas have formed by decompression melting of the mantle. Basalt has also formed on Earth's Moon, Mars,Venus, and even on the asteroid Vesta. The crustal portions of oceanic tectonic plates are composed predominantly of basalt, produced from upwelling mantle below ocean ridges.

Basalt is used for stone blocks

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