Rock Identifier

Category

Igneous Rock (Volcanic Glass)

Browse igneous rock (volcanic glass) specimens identified by the Rock Identifier community.

Blue Lace Agate (Silicon Dioxide (SiO₂), a variety of Chalcedony) — mineral

Blue Lace Agate

Silicon Dioxide (SiO₂), a variety of Chalcedony

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Granite (Granite) — igneous

Granite

Granite

Carnelian (Carnelian (a variety of Chalcedony, SiO

₂)) — Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)

Carnelian

Carnelian (a variety of Chalcedony, SiO ₂)

Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)

Quartz (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz

Quartz (SiO2 - Silicon Dioxide)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Quartzite (Quartzite (primarily SiO₂)) — metamorphic

Quartzite

Quartzite (primarily SiO₂)

Quartz pebble with surface markings (Silicon Dioxide (SiO2)) — mineral

Quartz pebble with surface markings

Silicon Dioxide (SiO2)

Wishing Stone (Greenschist or Basalt with Quartz/Calcite Vein) — metamorphic

Wishing Stone

Greenschist or Basalt with Quartz/Calcite Vein

Granite Pebble (Granite (Phaneritic Quartz-Feldspar intrusive rock)) — igneous

Granite Pebble

Granite (Phaneritic Quartz-Feldspar intrusive rock)

Coarse-grained Granite (Phaneritic Granite (contains Quartz, Feldspar, and Mica)) — igneous

Coarse-grained Granite

Phaneritic Granite (contains Quartz, Feldspar, and Mica)

Basalt with Quartz Veins (Basalt (SiO2 range 45-52%)) — igneous

Basalt with Quartz Veins

Basalt (SiO2 range 45-52%)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sandstone (with Iron Staining) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Chrysocolla in Matrix (Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4' nH2O on Quartz/Feldspar matrix) — mineral

Chrysocolla in Matrix

Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4' nH2O on Quartz/Feldspar matrix

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

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Sandstone (Pebble/Cobble) (Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)) — Sedimentary

Sandstone (Pebble/Cobble)

Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)

Gneiss (Gneissic Metamorphic Rock) — metamorphic

Gneiss

Gneissic Metamorphic Rock

Rhyolite (Rhyolite) — igneous

Rhyolite

Rhyolite

Granite (Granite (Felsic Plutonic Rock / SiO2 + Al2O3 + K2O + Na2O + CaO + FeO + MgO)) — igneous

Granite

Granite (Felsic Plutonic Rock / SiO2 + Al2O3 + K2O + Na2O + CaO + FeO + MgO)

Sandstone (Micaceous Sandstone) (Arenite (SiO2 with KAl2(AlSi3O10)(OH)2 inclusions)) — sedimentary

Sandstone (Micaceous Sandstone)

Arenite (SiO2 with KAl2(AlSi3O10)(OH)2 inclusions)

Olivine (Peridot) (Magnesium Iron Silicate ((Mg, Fe)2SiO4)) — mineral

Olivine (Peridot)

Magnesium Iron Silicate ((Mg, Fe)2SiO4)

Sandstone with Quartz Veins (Arenite (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone with Quartz Veins

Arenite (primarily SiO2 with Fe2O3 staining)

Chert (Nodule) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Carnelian Agate (Silicon dioxide (SiO2) - variety of Chalcedony) — mineral

Carnelian Agate

Silicon dioxide (SiO2) - variety of Chalcedony

Rose Quartz (Silicon Dioxide (SiO2)) — mineral

Rose Quartz

Silicon Dioxide (SiO2)

Blue Chalcedony (Silicon Dioxide (SiO2)) — mineral

Blue Chalcedony

Silicon Dioxide (SiO2)

Chalcedony (Agate/Quartz variety) (Cryptocrystalline Quartz (SiO2)) — mineral

Chalcedony (Agate/Quartz variety)

Cryptocrystalline Quartz (SiO2)

Chert (variations include Flint or Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (variations include Flint or Jasper)

Silicon Dioxide (SiO2)

Jasper (specifically Polychrome or Desert Jasper) (Silicon Dioxide (SiO2) with iron oxide and other mineral impurities) — sedimentary (chemical/biological origin)

Jasper (specifically Polychrome or Desert Jasper)

Silicon Dioxide (SiO2) with iron oxide and other mineral impurities

sedimentary (chemical/biological origin)

Jasper (Multi-color Chert) (Silicon dioxide (SiO2)) — sedimentary

Jasper (Multi-color Chert)

Silicon dioxide (SiO2)

Quartz in Matrix (possibly Basalt or Siltstone host) (Silicon Dioxide (SiO2) in Host Rock) — mineral

Quartz in Matrix (possibly Basalt or Siltstone host)

Silicon Dioxide (SiO2) in Host Rock

Agate Geode / Nodular Chalcedony (Silicon Dioxide (SiO2) with impurities) — mineral

Agate Geode / Nodular Chalcedony

Silicon Dioxide (SiO2) with impurities

Sandstone (with Iron concretions/staining) (Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)) — sedimentary

Sandstone (with Iron concretions/staining)

Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)

Banded Gneiss (Gneiss (Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (Metamorphic Rock)

Arkosic Sandstone (or Conglomeritic Sandstone fragment) (Arkose (rich in feldspar)) — sedimentary

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)

Yellow Quartz (Chalcedony) (Quartz / Chalcedony (Silicon Dioxide, SiO2)) — mineral

Yellow Quartz (Chalcedony)

Quartz / Chalcedony (Silicon Dioxide, SiO2)

Unakite (Unakite Epidosite (Granite with epidote and orthoclase)) — metamorphic

Unakite

Unakite Epidosite (Granite with epidote and orthoclase)

Fluorite with Quartz coating (Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)) — mineral

Fluorite with Quartz coating

Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)