What is the difference between granite and rhyolite? 1) Granite is an igneous rock, while rhyolite is a volcanic rock. 2) Granite is composed mainly of quartz and feldspar, while rhyolite is composed mainly of feldspar and quartz. 3) Granite is coarse-grained, while rhyolite is fine-grained. 4) Granite is intrusive, while rhyolite is extrusive.