Rock Identifier

Category

Glass

Browse glass specimens identified by the Rock Identifier community.

Learn about Glass in the encyclopedia

Sideromelane

Black Obsidian

Maskelynite

Tachylite

Obsidian

Hyalite Opal

Perlite

Opalite

Macusanite

Pink Obsidian

Goldstone

Palagonite

Agate and millefiori glass jewelry (Agate: microcrystalline quartz (SiO₂); millefiori element appears to be man-made glass) — mineral

Agate and millefiori glass jewelry

Agate: microcrystalline quartz (SiO₂); millefiori element appears to be man-made glass

Goldstone (Aventurine Glass (SiO2 + Cu small inclusions)) — man-made glass mineral simulant

Goldstone

Aventurine Glass (SiO2 + Cu small inclusions)

man-made glass mineral simulant

Obsidian with Mahogany Phasing (Volcanic Glass (SiO2 + Fe2O3)) — igneous

Obsidian with Mahogany Phasing

Volcanic Glass (SiO2 + Fe2O3)

Red Slag Glass (Amorphous Silica (Industrial byproduct with metallic oxide dopants)) — Mineraloid / Industrial Byproduct

Red Slag Glass

Amorphous Silica (Industrial byproduct with metallic oxide dopants)

Mineraloid / Industrial Byproduct

Pegmatite with Mica (Granitic Pegmatite (containing Muscovite and Biotite)) — igneous

Pegmatite with Mica

Granitic Pegmatite (containing Muscovite and Biotite)

Muscovite Schist with Quartz (KAl2(AlSi3O10)(OH,F)2 (Muscovite) in Schist) — metamorphic

Muscovite Schist with Quartz

KAl2(AlSi3O10)(OH,F)2 (Muscovite) in Schist

Tumbled yellow-brown quartzite or jasper (Quartzite, predominantly microcrystalline quartz (SiO₂), possibly iron-stained jasper) — metamorphic

Tumbled yellow-brown quartzite or jasper

Quartzite, predominantly microcrystalline quartz (SiO₂), possibly iron-stained jasper

Snowflake Obsidian (Spherulitic Obsidian (Amorphous Volcanic Glass with Cristobalite inclusions)) — igneous

Snowflake Obsidian

Spherulitic Obsidian (Amorphous Volcanic Glass with Cristobalite inclusions)

Chert (often called Flint or River Pebble) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (often called Flint or River Pebble)

Chert (Microcrystalline Quartz, SiO2)

Muscovite Mica (KAl2(AlSi3O10)(F,OH)2) — mineral

Muscovite Mica

KAl2(AlSi3O10)(F,OH)2

Dark flint or chert fragment (Microcrystalline quartz (SiO₂), commonly called flint when dark and nodular) — sedimentary

Dark flint or chert fragment

Microcrystalline quartz (SiO₂), commonly called flint when dark and nodular

Green Aventurine (SiO2 (Silicon Dioxide with Fuchsite inclusions)) — mineral

Green Aventurine

SiO2 (Silicon Dioxide with Fuchsite inclusions)

Muscovite Mica (with Quartz) (Muscovite (KAl2(AlSi3O10)(OH)2)) — mineral

Muscovite Mica (with Quartz)

Muscovite (KAl2(AlSi3O10)(OH)2)

Quartz with Muscovite Mica (SiO2 with KAl2(AlSi3O10)(OH)2) — mineral group

Quartz with Muscovite Mica

SiO2 with KAl2(AlSi3O10)(OH)2

Obsidian (Obsidian (Volcanic glass, primarily SiO2)) — igneous

Obsidian

Obsidian (Volcanic glass, primarily SiO2)

Muscovite Mica (KAl2(AlSi3O10)(F,OH)2) — mineral

Muscovite Mica

KAl2(AlSi3O10)(F,OH)2

Chert / Flint (Silicon Dioxide (SiO2)) — sedimentary

Chert / Flint

Silicon Dioxide (SiO2)

Libyan Desert Glass (Libyan Desert Glass (Impactite / High-silica Lechatelierite)) — mineral

Libyan Desert Glass

Libyan Desert Glass (Impactite / High-silica Lechatelierite)

Amethyst (Raw Quartz) (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst (Raw Quartz)

Silicon Dioxide (SiO2) with iron impurities

Opalite (likely man-made glass) (Opalite; amorphous silica glass, not a natural mineral) — gemstone

Opalite (likely man-made glass)

Opalite; amorphous silica glass, not a natural mineral

Snowflake Obsidian (Volcanic Glass (felsic volcanic glass with cristobalite inclusions)) — igneous

Snowflake Obsidian

Volcanic Glass (felsic volcanic glass with cristobalite inclusions)

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — gemstone

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Crackle Glass (Simulated Gemstone) (Amorphous Solid (SiO2)) — man-made glass

Crackle Glass (Simulated Gemstone)

Amorphous Solid (SiO2)

Rhinestone (Artificial Glass/Crystal) — gemstone

Rhinestone

Artificial Glass/Crystal

Blue Goldstone (Aventurine Glass (Silicon Dioxide with metal inclusions)) — man-made glass mineral simulant

Blue Goldstone

Aventurine Glass (Silicon Dioxide with metal inclusions)

man-made glass mineral simulant

Blue glass-like cabochon, likely dyed or synthetic material (Uncertain; possibly dyed chalcedony, synthetic spinel, or blue glass) — gemstone

Blue glass-like cabochon, likely dyed or synthetic material

Uncertain; possibly dyed chalcedony, synthetic spinel, or blue glass

Fulgurite (Fulgurite (Lechatelierite or fused sand/quartz)) — mineral

Fulgurite

Fulgurite (Lechatelierite or fused sand/quartz)

Polished black stone, likely obsidian (Volcanic glass; chiefly amorphous SiO₂) — igneous

Polished black stone, likely obsidian

Volcanic glass; chiefly amorphous SiO₂

Obsidian (Volcanic Glass (SiO2 + minor impurities)) — igneous

Obsidian

Volcanic Glass (SiO2 + minor impurities)

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

Quartz (Clear Quartz)

Silicon Dioxide (SiO2)

Snowflake Obsidian (Polished Cabochon) (Obsidian with Spherulitic Cristobalite (SiO2)) — igneous

Snowflake Obsidian (Polished Cabochon)

Obsidian with Spherulitic Cristobalite (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Blue Goldstone (Goldstone (artificial glass)) — Mineral (man-made glass, not natural)

Blue Goldstone

Goldstone (artificial glass)

Mineral (man-made glass, not natural)

Goldstone (Aventurine Glass (Man-made glass with copper inclusions)) — mineraloid / man-made glass

Goldstone

Aventurine Glass (Man-made glass with copper inclusions)

mineraloid / man-made glass

Tumbled pink quartz (probable rose quartz) (Quartz, silicon dioxide (SiO₂), likely rose quartz variety) — mineral

Tumbled pink quartz (probable rose quartz)

Quartz, silicon dioxide (SiO₂), likely rose quartz variety

Possibly tumbled black stone (uncertain; may be black glass or obsidian) (Undetermined; possible obsidian (natural volcanic glass, predominantly SiO₂)) — mineral

Possibly tumbled black stone (uncertain; may be black glass or obsidian)

Undetermined; possible obsidian (natural volcanic glass, predominantly SiO₂)

Polished jasper/chalcedony nodule (Microcrystalline quartz (SiO₂), likely jaspery chalcedony with iron-oxide staining) — mineral

Polished jasper/chalcedony nodule

Microcrystalline quartz (SiO₂), likely jaspery chalcedony with iron-oxide staining

Tumbled black stone, likely black obsidian (Obsidian — natural volcanic glass, predominantly silica-rich rhyolitic composition) — igneous

Tumbled black stone, likely black obsidian

Obsidian — natural volcanic glass, predominantly silica-rich rhyolitic composition

Chert (Quartz) (Silicon dioxide (SiO2)) — sedimentary

Chert (Quartz)

Silicon dioxide (SiO2)

Green Aventurine (Quartz containing Fuchsite (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)) — mineral

Green Aventurine

Quartz containing Fuchsite (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

Muscovite Mica (Muscovite, KAl2(AlSi3O10)(OH)2) — mineral

Muscovite Mica

Muscovite, KAl2(AlSi3O10)(OH)2

Muscovite (Muscovite (KAl2(AlSi3O10)(OH)2)) — mineral

Muscovite

Muscovite (KAl2(AlSi3O10)(OH)2)