15 Ways We Use Rocks
For rockhounds, rocks can be fascinating even if they aren't useful. Thundereggs, agates, quartz—they all have cool names and they're shiny. Throughout history, however, rocks have been used for many, many different purposes. In my previous post, I mentioned my family's rockhound neighbor , back when I was a kid. This neighbor taught one of my brothers how to polish rocks and introduced my family to a variety of different types of rocks. One of those rocks was obsidian. Obsidian has fascinated me ever since then—it’s a rock, but it’s also glass? As I’ve learned more recently, obsidian isn’t just a plain, black, glassy rock. It can have snowflake patterns or rainbow colors. Because it is glass, obsidian breaks in a curving “conchoidal” fracture. And because it breaks into pieces with thin edges, it’s been used to create knives, arrowheads, and other sharp tools. Rocks like obsidian were one of the first materials that humans used to make tools, but humans have used
