Question:
How do I identify volcanic rocks?
Glassy Rocks
If a rock seems to have a "glassy" texture, that is, you're pretty sure there's no mineral grains in it, it is probably a volcanic igneous rock.
Pumice is a volcanic igneous rock that is full of tiny holes and is so light small samples of it will float on water. Scoria is a glassy igneous rock that is usually dark-colored and full of dark holes.
Obsidian is a volcanic glassy rock that has no holes, and a shiny appearance, as if it were made of glass.
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| Guru Spotlight |
| Sherril Steele-Carlin |
