Basalt - Geology for Kids - what is basalt made of? why is basalt so hard?
SIGN IN / SUBSCRIBE TO KIDIPEDE
LOG OUT


Basalt

Basalt

Basalt is a fine-grained, hard rock that forms when bits of lava shoot out of volcanoes, so it's one kind of igneous rock. When the lava cools quickly, it turns into basalt. Usually basalt is black or gray. Basalt is a mixture of feldspar and pyroxene, a rock made mainly of silica and oxygen. Pyroxene is what jade is before metamorphosis.

Basalt is pretty common on Earth, and there is also a lot of basalt on the Moon, and on other planets including Mars and Venus.

Asphalt pavement
Asphalt pavement made with basalt

Like granite, basalt is a very hard rock. Because it is a common rock and so hard, people used basalt for early choppers and for grinding stones for grinding grains like millet and barley. Roman engineers paved a lot of Roman roads with basalt, and today engineers still use a lot of ground-up basalt to make asphalt to pave roads.

To find out more about rocks, check out these books from Amazon.com or from your library:

More about Basalt
Granite
Feldspar
Quartz
Volcanoes
Rocks
Geology home page
Science for Kids home page
Kidipede home page



Copyright 2012-2014 Karen Carr, Portland State University. This page last updated 2014. Powered by Dewahost.
About - Contact - Privacy Policy - What do the broom and the mop say when you open the closet door?
-->