Rhyolite
igneous, volcanic rock, of felsic (silica-rich) composition
Rhyolite is a very strong igneous, volcanic rock.
![](http://up.wiki.x.io/wikipedia/commons/thumb/7/7e/RhyoliteUSGOV.jpg/220px-RhyoliteUSGOV.jpg)
German geologist Ferdinand von Richthofen named the rock.
Rhyolite is a very strong igneous, volcanic rock.
German geologist Ferdinand von Richthofen named the rock.