which characteristic is common to extrusive igneous rocks?

Extrusive igneous rocks are commonly characterized by having small (fine‑grained) or even microscopic crystals because they cool very quickly at or near Earth’s surface.

Quick Scoop

• They form when lava erupts onto the surface and cools rapidly, so minerals do not have time to grow large crystals.

• This rapid cooling gives them a fine‑grained (aphanitic) or sometimes glassy texture that looks fairly uniform to the naked eye.

• Many extrusive rocks can also contain vesicles, which are small holes left by trapped volcanic gas, but the truly common, shared feature is their small crystal size from rapid cooling.

So, if you see a volcanic rock that looks smooth or very tiny‑grained with crystals too small to see clearly, that fine‑grained texture is the key characteristic typical of extrusive igneous rocks.

Information gathered from public forums or data available on the internet and portrayed here.