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Obsidian/Volcanic Glass
Obsidian is a naturally occurring volcanic glass formed when lava cools rapidly and lacks crystalline structure. It is primarily composed of silica, usually over 70%, with other elements such as aluminum, iron, magnesium, and potassium. Here are some key characteristics of obsidian rocks: Color: Obsidian typically has a shiny, jet-black...
Obsidian: When Lava Turns to Glass
Glossy, dark, and sometimes almost mirror-like, Obsidian is instantly recognizable. At first glance, it can look more like a piece of black glass than something created by a volcano. And that's because, in a way, it is. Obsidian is a naturally occurring volcanic glass that forms when certain types of...