My husband, Mark, is a geophysicist. He loves learning why a certain rock is located where it is within nature, and the forces that colored and shaped it. Me, I just love the end result of all those geological activities. He can divide and subdivide rocks into dozens of categories. He claims, “the rocks talk to me and tell me their history, the why and how.” For me there are only three categories of geology: pretty, not pretty but interesting, and not pretty and not interesting. I’m sure you’ll have your own characterizations of these natural formations.