Uuuuuummmm... Sir? Can you help me learn about Igneous rocks?
Yes, we will start with Intrusive and Extrusive rocks. Intrusive rocks come from inside the Earth or magma inside a volcano. Also, they can have large crystals.
Extrusive rocks come from outside the volcano or the lava on the ground. They can have small or no crystals and can be vesicular. (Which means it has air bubbles like Pumice.) Pumice has air bubbles and is light in weight.
OK........ now what?
Granite is an Intrusive rock because it has visible minerals or there larger than 1 mm. Obsidian is Extrusive because it has no crystals and it is also a dark color.
Now we will learn about color. A rocks color is determined by its silica amount. If the rock has low silica it is dark in color like Obsidian.
If the rock has high silica it is light in color like Pumice.
Thanks for helping me learn about Igneous rocks..... CREEPY GUY