igneous
Basalt Pebble
Extrusive Igneous Rock
Hardness of 6 on the Mohs scale, dark gray to black color, fine-grained (aphanitic) texture, dull luster, composed primarily of plagioclase feldspar and pyroxene.
Identified More igneous →
Explore Basalt Pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 6 on the Mohs scale, dark gray to black color, fine-grained (aphanitic) texture, dull luster, composed primarily of plagioclase feldspar and pyroxene.
Formation & geological history
Formed from the rapid cooling of mafic lava exposed at or very near the Earth's surface. This particular specimen has been smoothed and rounded by water transport in a river or beach environment.
Uses & applications
Used in landscaping, construction aggregates, and decorative stones.
Geological facts
Basalt is the most common rock type on Earth's crust beneath the oceans and also makes up significant portions of the lunar maria and the surface of Mars.
Field identification & locations
Easily identified by its dark, fine-grained appearance and heavy feel for its size. Common in volcanic regions, riverbeds, and shorelines worldwide.
