1. Basalt: This is a dark-colored, dense, and fine-grained volcanic rock. It is typically formed from quickly cooling lava flows. You'll often find basalt in oceanic crust and volcanic regions.

2. Rhyolite: This is a light-colored, fine-grained igneous rock that is formed from slowly cooling lava. It is often found in areas of continental crust where volcanoes have erupted. Rhyolite can be glassy or contain small crystals.