Related Clues:
- Mineral resistant to heat
- Flaking rock
- Thin mineral sheet
- Countertop material
- Glittery mineral
- Mineral that crystallizes from magma
- Isinglass, e.g.
- Watch crystal, maybe
- Mineral that forms in sheets
- Isin-glass
- Mineral with basal cleavage
- What a crystal ball gazer sees
- Mineral noted for its cleavage
- Hard glossy mineral present in many rocks
- A hard mineral, found in watches