universetoday.com
Obsidian
[/caption] Did you know that volcanoes can make glass? Well, it’s not exactly the kind of glass you’d want to put in your house. It’s called obsidian, and it’s a naturally occurring volcanic glass formed when felsic lava flows from a volcano and then cools without crystal growth. In a regular eruption, lava pours out … Continue reading "Obsidian"
Fraser Cain