Andesite is an extrusive igneous volcanic rock which is in between rhyolite and basalt. Texture of andesite is between aphanitic and porphyritic. Andesite is fine grained rock. Andesite lava is of moderate viscosity and forms thich lava flows and domes. Andesite is mainly composed of plagioclase with other minerals such as hornblende, pyroxene and biotite. It is volcanic equivalent of diorite.
Colour of andesite varies between bluish grey to grey but is lighter colour than of the basalt.
Andesite can be used as a crushed aggregate in construction but is not often choose to be ideal because of the high silica content.