Related Clues:
- Moon rock makeup
- Dark igneous rock
- Dense volcanic rock
- Certain igneous rock
- Volcanic glass
- A hard black volcanic glass
- Dark volcanic rock
- Dark rock of volcanic origin
- Type of rock is a blast, oddly
- Dark glassy rock formed from lava
- It takes a saline degree to make a rock of this
- To a degree the sailor gets stoned, perhaps
- Rock to a certain degree over the sailor
- No bid is a rock like this
- Kind of igneous rock