| Rock Class | igneous rock |
|
Rock Subclass
|
Volcanic (volcanic glass) |
| Origin | Hidalgo, Mexico |
| Size |
Medium: 3.00-4.00 cm Large: 4.00-5.00 cm |
Obsidian, or volcanic glass, is molten lava that has cooled rapidly. Its composition is mainly of silicic oxides, being very similar to that of granite or rhyolite.
Snowy or snowflake obsidian is a variety that presents circular white-gray spots, called spherulites.
The piece you receive may differ slightly from the photo shown as the rocks are natural and no piece is identical. The size is approximate.