There are over 5,000 known types of minerals ... Rocks also differ based on how they were formed. Igneous rocks form out of cooling lava or magma. Sedimentary rocks develop from eroded grains ...

Rhyolitic lava flows are volcanic flows composed of rhyolite — a high-silica (over 70% SiO2) volcanic rock. This type of lava ...

The type of lava erupted by Nyiragongo and many volcanoes ... of magma that cut through and across the layering of adjacent rocks and then solidify. They form when magma rises into a fissure ...

Composite volcanoes are the most common type of volcano ... ll need to watch out for things like lava flow. Lava is very hot molten or liquid rock, which reaches over 1,000 degrees.