Here's why:

* Granite is an igneous rock that forms deep underground (intrusive) and cools slowly, resulting in large mineral crystals.

* Rhyolite is an igneous rock that forms from volcanic eruptions (extrusive) and cools quickly, leading to smaller crystals.

Both rocks have a similar chemical composition, primarily consisting of quartz, feldspar, and mica. The main difference is their cooling rate and the resulting crystal size.