Rock Identifier

Category

Mineral Like (Natural Glass)

Browse mineral like (natural glass) specimens identified by the Rock Identifier community.

Sandstone (Arenite (SiO2 primarily)) — sedimentary

Sandstone

Arenite (SiO2 primarily)

Obsidian (specifically Mahogany Obsidian) (Volcanic glass (high silica content, SiO2)) — igneous

Obsidian (specifically Mahogany Obsidian)

Volcanic glass (high silica content, SiO2)

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

Quartz (Clear Quartz)

Silicon Dioxide (SiO2)

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

Muscovite

Muscovite (KAl2(AlSi3O10)(OH)2)

Pearl (Biogenic CaCO3 (Aragonite)) — mineral

Pearl

Biogenic CaCO3 (Aragonite)

Milky Quartz with Iron Staining (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Shale (Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)) — sedimentary

Shale

Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Quartz (Milky or Citrine-tinted) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky or Citrine-tinted)

Silicon Dioxide (SiO2)

Smoky Quartz (SiO2 (Silicon Dioxide)) — mineral

Smoky Quartz

SiO2 (Silicon Dioxide)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Obsidian (Extrusive igneous volcanic glass) — igneous

Obsidian

Extrusive igneous volcanic glass

Obsidian (Obsidian (Amorphous volcanic glass)) — igneous

Obsidian

Obsidian (Amorphous volcanic glass)

Green Aventurine (Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)) — metamorphic

Green Aventurine

Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

Snowflake Obsidian (Volcanic glass with Cristobalite inclusions (mostly SiO2)) — igneous

Snowflake Obsidian

Volcanic glass with Cristobalite inclusions (mostly SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

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

Muscovite Mica (with Quartz matrix)

Muscovite - KAl2(AlSi3O10)(OH)2

Mica (Muscovite) (Potassium aluminum silicate - KAl2(AlSi3O10)(OH)2) — mineral

Mica (Muscovite)

Potassium aluminum silicate - KAl2(AlSi3O10)(OH)2

Jasper and Agate (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper and Agate

Microcrystalline Quartz (SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Mahogany Obsidian (Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)

Citrine (Silicon Dioxide (SiO2)) — mineral

Citrine

Silicon Dioxide (SiO2)

Feldspar (Orthoclase) (Orthoclase Feldspar (KAlSi3O8)) — mineral

Feldspar (Orthoclase)

Orthoclase Feldspar (KAlSi3O8)

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

Clear Quartz (Carved Dragon)

Quartz (Silicon Dioxide, SiO2)

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

Snowflake Obsidian

Obsidian with Spherulitic Cristobalite (SiO2)

Snowflake Obsidian (Volcanic Glass with Cristobalite inclusions) — igneous

Snowflake Obsidian

Volcanic Glass with Cristobalite inclusions

Dyed Agate (Tumbled) (Silicon Dioxide (SiO2) - stained microcrystalline quartz) — sedimentary

Dyed Agate (Tumbled)

Silicon Dioxide (SiO2) - stained microcrystalline quartz

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

Sapphire (Raw/Rough)

Corundum (Al2O3)

Quartzite (Quartzite (SiO2 principal component)) — metamorphic

Quartzite

Quartzite (SiO2 principal component)

Black Obsidian (Volcanic Glass (SiO2 + impurities like Fe3O4)) — igneous

Black Obsidian

Volcanic Glass (SiO2 + impurities like Fe3O4)

Diamond (Carbon (C)) — mineral

Diamond

Carbon (C)

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

Muscovite Mica

KAl2(AlSi3O10)(F,OH)2

Quartz (specifically Milky or Clear Quartz fragment) (Silicon Dioxide (SiO2)) — mineral

Quartz (specifically Milky or Clear Quartz fragment)

Silicon Dioxide (SiO2)

Agate (Agate (a variety of Chalcedony, SiO2)) — Mineral

Agate

Agate (a variety of Chalcedony, SiO2)

Sandstone (Clastic Sedimentary Rock (primarily Quartz, SiO2)) — sedimentary

Sandstone

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Red Quartzite / River Siltstone (Quartzite (SiO2 with iron oxide inclusions)) — metamorphic

Red Quartzite / River Siltstone

Quartzite (SiO2 with iron oxide inclusions)

Obsidian (Obsidian (Volcanic Glass, SiO2 + impurity)) — Igneous

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurity)

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

Rough Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Iron Ore (Limonite and Hematite) (Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)) — mineral

Iron Ore (Limonite and Hematite)

Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)

Diamond (Carbon (C)) — mineral

Diamond

Carbon (C)

Diamond (Carbon (C)) — mineral

Diamond

Carbon (C)