Crystal type, cleavage, and hardness are established mainly because of the crystal structure on the atomic stage. Exceptionally common while in the Earth's crust, igneous rocks are volcanic and type from molten material. They involve don't just lava spewed from volcanoes, but also rocks like granite, that are formed by https://bookmarkspy.com/story2310940/the-5-second-trick-for-rock-cycle-videos