Obsidian
Amorphous volcanic glass (SiO2)
Category
Browse mineral (man made glass, not natural) specimens identified by the Rock Identifier community.
Obsidian
Amorphous volcanic glass (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Granite Cobble (River Stone)
Felsic intrusive igneous rock (composition: Quartz, Feldspar, Mica)
Milky Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Green Aventurine (Tumbled Quartz)
Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)3Si3O10(OH)2)
Mahogany Obsidian
Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Obsidian
Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)
Obsidian
Obsidian (Volcanic Glass, SiO2 dominated)
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lithium-bearing mica)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Lodolite (Garden Quartz)
Silicon Dioxide (SiO2) with inclusions (Chlorite, Hematite, etc.)
Rose Quartz
Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Quartz Pebble (Iron-Stained)
Silicon Dioxide (SiO2)
Quartz (Milky or Cloudy Quartz)
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Jasper
Jasper (Silica/Silicon Dioxide, SiO2)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Mahogany Obsidian
Volcanic Glass (SiO2 + Fe2O3)
Beach Agate (Chalcedony)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Fluorite
Calcium Fluoride (CaF2)
Rose Quartz
Silicon Dioxide (SiO2)
Orthoclase Feldspar
Potassium aluminum silicate (KAlSi3O8)
Red Jasper (River pebble)
Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)
White Quartz Sphere
Silicon Dioxide (SiO2)
Fluorite
Calcium Fluoride (CaF2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz (Water-Worn Pebble)
Silicon Dioxide (SiO2)
Orthoclase Feldspar with Quartz
Orthoclase (KAlSi3O8)
Amazonite
KAlSi3O8 (Potassium Feldspar, variety of Microcline)
Tiger's Eye
Tiger's Eye (a variety of Chalcedony, which is a microcrystalline quartz with fibrous inclusions of oxidized crocidolite)
Clear Quartz
Silicon Dioxide (SiO2) / Rock Crystal
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Pink Granite
Granite (Phaneritic Quartz-Feldspar Rock)
Quartz with Hematite Staining
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3) inclusions
Sandstone (with Limonite staining)
Arenite (primarily SiO2 with FeO(OH)·nH2O)
Fluorite (Rainbow/Purple Fluorite)
Calcium Fluoride (CaF2)
Quartz (specifically Milky or Rose Quartz)
Silicon Dioxide (SiO2)