Igneous Rocks and Associated Minerals

Click on the underlined links in the tables below to obtain more information about the igneous rock, texture or mineral, including some specimen pictures.

Igneous Rocks and Glasses

andesite gabbro obsidian rhyolite
basalt granite pumice tuff

Textures associated with igneous rocks

aphanitic: very fine grained

glassy: texture of broken glass

phaneritic: mineral grains are coarse/large enough to be distinct

porphyritic: larger grains in a finer-grained matrix or ground mass

pyroclastic: "fire broken" or blasted from a volcano

scoriaceous: low-density rock with very large number of small gas-bubble voids

vesicular: with gas-bubble voids frozen in rock at time of crystallization

Minerals commonly associated with igneous rocks

alkalai feldspar


plagioclase feldspar





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