|
Hard- ness |
Cleavage |
Fracture |
Trans- parency |
10% HCl Reaction |
SG |
Luster |
Color |
Streak |
Xtal Form |
Mineral Class |
Comments | obsidian | 5.50 | none | conchoidal | Transparent | none | 2.65 | glassy | black | white | microcrystalline | silicates | Not a mineral but common in felsic volcanic regions. Clear to black with inclusions of rock, minerals or air bubbles. |
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