Rock Identifier

Category

Mineraloid (Man Made Glass)

Browse mineraloid (man made glass) specimens identified by the Rock Identifier community.

Learn about Mineraloid (Man Made Glass) in the encyclopedia

Opalite

Goldstone

Shungite

Blue Goldstone

Sideromelane

Black Obsidian

Maskelynite

Tachylite

Obsidian

Map Jasper

Hyalite Opal

Perlite

Green Opal (Hydrated Silica (SiO2·nH2O)) — mineraloid

Green Opal

Hydrated Silica (SiO2·nH2O)

Precious Opal (Hydrated Silica (SiO2·nH2O)) — mineral

Precious Opal

Hydrated Silica (SiO2·nH2O)

Limonite/Ironstone (Limonite (FeO(OH)·nH2O)) — mineral

Limonite/Ironstone

Limonite (FeO(OH)·nH2O)

Limonite (Iron Ore) (Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)

Jet (Lignite (Anthracite-grade compact coal)) — sedimentary

Jet

Lignite (Anthracite-grade compact coal)

Chert (Flint/Jasper variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint/Jasper variety)

Microcrystalline Quartz (SiO2)

Blue glassy cabochon, likely blue quartz or synthetic glass (Possibly dyed blue chalcedony/quartz (SiO₂); visual identification is inconclusive) — gemstone

Blue glassy cabochon, likely blue quartz or synthetic glass

Possibly dyed blue chalcedony/quartz (SiO₂); visual identification is inconclusive

Black-and-white agate geode pendant (Agate (microcrystalline quartz, SiO₂), likely a hollow geode slice with chalcedony and drusy quartz) — mineral

Black-and-white agate geode pendant

Agate (microcrystalline quartz, SiO₂), likely a hollow geode slice with chalcedony and drusy quartz

Obsidian (Volcanic Glass (Amorphous Silicon Dioxide)) — igneous

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Opal (Hydrated Silica (SiO2·nH2O)) — mineral

Opal

Hydrated Silica (SiO2·nH2O)

Limonite (Ironstone) (Limonite (mixture of hydrated iron(III) oxide-hydroxides)) — mineral

Limonite (Ironstone)

Limonite (mixture of hydrated iron(III) oxide-hydroxides)

Obsidian (Volcanic glass) — igneous

Obsidian

Volcanic glass

Red glass-like crystal, likely synthetic ruby or red glass (Uncertain from image; possible corundum (ruby), Al₂O₃, or synthetic glass) — gemstone

Red glass-like crystal, likely synthetic ruby or red glass

Uncertain from image; possible corundum (ruby), Al₂O₃, or synthetic glass

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

Chert (Flint)

Silicon Dioxide (SiO2)

Polished amethyst-bearing quartz (Quartz, SiO₂; purple coloration from irradiation and trace iron) — mineral

Polished amethyst-bearing quartz

Quartz, SiO₂; purple coloration from irradiation and trace iron

Opal (in Jewelry Setting) (Hydrated Silicon Dioxide (SiO2·nH2O)) — gemstone

Opal (in Jewelry Setting)

Hydrated Silicon Dioxide (SiO2·nH2O)

Opal (Hydrated Amorphous Silica (SiO2·nH2O)) — Mineral

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Pink Granite (Phaneritic Felsic Igneous Rock (Granite)) — igneous

Pink Granite

Phaneritic Felsic Igneous Rock (Granite)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Granodiorite (Granodiorite) — Igneous

Granodiorite

Granodiorite

Green Aventurine (Silicon Dioxide (SiO2+KAl2(AlSi3O10)(OH)2)) — metamorphic

Green Aventurine

Silicon Dioxide (SiO2+KAl2(AlSi3O10)(OH)2)

Tumbled blue chalcedony (possibly blue agate) (Microcrystalline quartz, SiO₂; chalcedony variety) — mineral

Tumbled blue chalcedony (possibly blue agate)

Microcrystalline quartz, SiO₂; chalcedony variety

Beaded gemstone bracelet (Indeterminate; likely small polished mineral beads, possibly turquoise or dyed stone, with metal and glass components) — gemstone

Beaded gemstone bracelet

Indeterminate; likely small polished mineral beads, possibly turquoise or dyed stone, with metal and glass components

Diamond (in a gold ring) (Diamond (pure carbon, C)) — mineral

Diamond (in a gold ring)

Diamond (pure carbon, C)

Opal (Hydrated silica (SiO2 "NH2O)) — mineraloid

Opal

Hydrated silica (SiO2 "NH2O)

Amber (Amber (C10H16O)) — mineral

Amber

Amber (C10H16O)

Opal (Hydrated amorphous silica (SiO2·nH2O)) — mineral

Opal

Hydrated amorphous silica (SiO2·nH2O)

Black Pearl (Tahitian Pearl) (Aragonite / Calcite (CaCO3) with Conchiolin) — mineral

Black Pearl (Tahitian Pearl)

Aragonite / Calcite (CaCO3) with Conchiolin

Limonite (Iron Ore) (FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)) — mineral

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)

Obsidian (Volcanic glass (SiO2)) — igneous

Obsidian

Volcanic glass (SiO2)

Rough Sapphire (Corundum) (Corundum (Al2O3)) — mineral

Rough Sapphire (Corundum)

Corundum (Al2O3)

Tumbled amber (Amber (fossilized plant resin), commonly succinite; organic mineraloid) — gemstone

Tumbled amber

Amber (fossilized plant resin), commonly succinite; organic mineraloid

Obsidian (Volcanic glass (SiO2 - Silicon Dioxide)) — igneous

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide)

Tumbled green glassy mineral, possibly aventurine or fluorite (Uncertain; likely quartz variety (aventurine quartz, SiO₂) or green fluorite (CaF₂)) — mineral

Tumbled green glassy mineral, possibly aventurine or fluorite

Uncertain; likely quartz variety (aventurine quartz, SiO₂) or green fluorite (CaF₂)

Chert (Chert (Microcrystalline Quartz)) — sedimentary

Chert

Chert (Microcrystalline Quartz)

Diamond (Carbon (C)) — gemstone

Diamond

Carbon (C)

Green obsidian (likely moldavite) (Natural volcanic glass; if extraterrestrial-impact glass, moldavite (tektite)) — gemstone

Green obsidian (likely moldavite)

Natural volcanic glass; if extraterrestrial-impact glass, moldavite (tektite)

Limonite (Iron Stone/Ocher) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Iron Stone/Ocher)

Limonite (FeO(OH)·nH2O)

Limonite/Goethite on Shale (Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock) — sedimentary

Limonite/Goethite on Shale

Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock

Red cabochon gemstone ring (likely ruby or red spinel; identity unconfirmed) (Possibly corundum (ruby, Al₂O₃) or spinel (MgAl₂O₄); visual identification alone cannot distinguish these from glass or synthetic stones.) — gemstone

Red cabochon gemstone ring (likely ruby or red spinel; identity unconfirmed)

Possibly corundum (ruby, Al₂O₃) or spinel (MgAl₂O₄); visual identification alone cannot distinguish these from glass or synthetic stones.

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

Chert or Jasper

Microcrystalline Quartz (SiO2)

Flint (SiO2 (Cryptocrystalline Quartz)) — sedimentary

Flint

SiO2 (Cryptocrystalline Quartz)