| Rock Class | igneous rock |
|
Rock Subclass
|
Volcanic (volcanic glass) |
| Origin | Hidalgo, Mexico |
| Size | 2.0-3.0cm |
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 rock includes a label with the name and origin and is glued in a cardboard box 4 cm square.
*The price is per unit (a single cardboard box of the four shown in the image)
Since the rocks are natural, you will receive a piece similar to the one in the photograph. The samples come in cardboard boxes and are glued to a porex base with hot silicone; these can be removed using ethyl alcohol without damaging the mineral. The size is approximate.