Rock Identifier

Category

Glass

Browse glass specimens identified by the Rock Identifier community.

Learn about Glass in the encyclopedia

Sideromelane

Black Obsidian

Maskelynite

Obsidian

Tachylite

Hyalite Opal

Perlite

Opalite

Macusanite

Pink Obsidian

Goldstone

Palagonite

Mica (Biotite or Phlogopite variety) (Phyllosilicate (complex mineral formula involving K, Mg, Fe, Al, Si, and O)) — mineral

Mica (Biotite or Phlogopite variety)

Phyllosilicate (complex mineral formula involving K, Mg, Fe, Al, Si, and O)

Obsidian (Volcanic Glass (SiO2 - Silicon Dioxide with impurities)) — igneous

Obsidian

Volcanic Glass (SiO2 - Silicon Dioxide with impurities)

Pumice (Pumice) — igneous

Pumice

Pumice

Clear Quartz (Silicon dioxide (SiO2)) — mineral

Clear Quartz

Silicon dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Green glassy mineral fragment, possibly fluorite (Fluorite (calcium fluoride, CaF₂), tentative identification) — mineral

Green glassy mineral fragment, possibly fluorite

Fluorite (calcium fluoride, CaF₂), tentative identification

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Quartz (Clear or Smoky) (Silicon Dioxide (SiO2)) — mineral

Quartz (Clear or Smoky)

Silicon Dioxide (SiO2)

Milky Quartz Pebble with Matrix (Quartz (SiO2)) — mineral

Milky Quartz Pebble with Matrix

Quartz (SiO2)

Quartz (Milky/Common) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Quartz (Milky/Clear) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Clear)

Silicon Dioxide (SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Small pale mineral fragment, likely quartz or calcite (Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing) — mineral

Small pale mineral fragment, likely quartz or calcite

Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing

Rounded pebble, likely quartz-rich sandstone or chert (Indeterminate lithic clast; possibly quartz arenite or microcrystalline quartz (SiO₂)) — sedimentary

Rounded pebble, likely quartz-rich sandstone or chert

Indeterminate lithic clast; possibly quartz arenite or microcrystalline quartz (SiO₂)

Muscovite Mica (Granitic Pegmatite) (Muscovite - KAl2(AlSi3O10)(OH)2) — igneous

Muscovite Mica (Granitic Pegmatite)

Muscovite - KAl2(AlSi3O10)(OH)2

Smoky Quartz (Smoky Quartz (Silicon Dioxide, SiO2)) — mineral

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)

Quartz / Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz / Milky Quartz

Silicon Dioxide (SiO2)

Quartz / Common Opal (Silicon Dioxide (SiO2)) — mineral

Quartz / Common Opal

Silicon Dioxide (SiO2)

Obsidian (likely black volcanic glass) (Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition) — igneous

Obsidian (likely black volcanic glass)

Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition

Mixed Tumbled Quartz and Chlorite Quartz (Silicon Dioxide (SiO2) with inclusions) — mineral

Mixed Tumbled Quartz and Chlorite Quartz

Silicon Dioxide (SiO2) with inclusions

Quartz Drusy on Matrix (Silicon Dioxide (SiO2)) — mineral

Quartz Drusy on Matrix

Silicon Dioxide (SiO2)

Obsidian (Volcanic Glass (70-75% SiO2)) — igneous

Obsidian

Volcanic Glass (70-75% SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Quartz crystal fragment (likely milky/inclusion-rich quartz) (Quartz, silicon dioxide (SiO₂)) — mineral

Quartz crystal fragment (likely milky/inclusion-rich quartz)

Quartz, silicon dioxide (SiO₂)

Smoky Quartz with Feldspar (Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)) — mineral

Smoky Quartz with Feldspar

Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)

Quartz (Clear Quartz/Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Flint or Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Flint or Chert

Microcrystalline Quartz (SiO2)

Clear Quartz (Tumbled) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Tumbled)

Silicon Dioxide (SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Quartz (Smoky Quartz variant) (Silicon Dioxide (SiO2)) — mineral

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Pumice (Pumice (Volcanic glass / Felsic igneous rock)) — igneous

Pumice

Pumice (Volcanic glass / Felsic igneous rock)

Quartz (Smoky/Grey variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Smoky/Grey variety)

Silicon Dioxide (SiO2)

Green Obsidian Sphere (man-made glass) (Vitreous Silica with Chromium/Iron additives) — mineralogical simulant

Green Obsidian Sphere (man-made glass)

Vitreous Silica with Chromium/Iron additives

mineralogical simulant

Goldstone (Brown/Gold) (Aventurine Glass (Man-made glass with Copper inclusions)) — gemstone

Goldstone (Brown/Gold)

Aventurine Glass (Man-made glass with Copper inclusions)

Tumbled black obsidian (Obsidian (volcanic glass), primarily rhyolitic silica glass) — igneous

Tumbled black obsidian

Obsidian (volcanic glass), primarily rhyolitic silica glass

Black Obsidian (Volcanic Glass (felsic volcanic glass, rich in SiO2)) — igneous

Black Obsidian

Volcanic Glass (felsic volcanic glass, rich in SiO2)

Chert (Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Chert (often called Flint) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (often called Flint)

Microcrystalline quartz (SiO2)

Clear Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Citrine Quartz (Silicon Dioxide (SiO2) with iron impurities) — mineral

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities