Rock Identifier

Category

Sedimentary Or Igneous (Secondary Formation)

Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.

Opal (Hydrous silicon dioxide (SiO2·nH2O)) — mineral

Opal

Hydrous silicon dioxide (SiO2·nH2O)

Gneiss (Schistose) (Gneiss) — metamorphic

Gneiss (Schistose)

Gneiss

Carnelian (Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)) — Mineral

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)

Biotite (Mica) (Biotite group (K(Mg,Fe)3AlSi3O10(F,OH)2)) — mineral

Biotite (Mica)

Biotite group (K(Mg,Fe)3AlSi3O10(F,OH)2)

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

Quartz (Milky/Vein Quartz)

Silicon Dioxide (SiO2)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Biotite Schist (Biotite-rich Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)) — metamorphic

Biotite Schist

Biotite-rich Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)

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

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Pyrite (Fool's Gold) (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Banded Gneiss (Gneiss (High-grade regional metamorphic rock)) — metamorphic

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Pyrite (on Quartz/Host Rock) (Iron Sulfide (FeS₂)) — mineral

Pyrite (on Quartz/Host Rock)

Iron Sulfide (FeS₂)

Yellow Quartz (Citrine or Yellow Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine or Yellow Chalcedony)

Silicon Dioxide (SiO2)

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

Quartz (Milky or Clear Quartz fragment)

Silicon Dioxide (SiO2)

Carnelian (Orange Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Carnelian (Orange Chalcedony)

Silicon Dioxide (SiO2)

Marble (Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).) — Metamorphic Rock

Marble

Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).

Metamorphic Rock

Banded Gneiss (Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica)) — metamorphic

Banded Gneiss

Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica)

Quartz (specifically Milky Quartz Pebble) (Silicon Dioxide (SiO2)) — mineral

Quartz (specifically Milky Quartz Pebble)

Silicon Dioxide (SiO2)

Quartz (Iron-stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Phantom Quartz with Chlorite and Hematite inclusions (Silicon Dioxide (SiO2) with inclusions of Chlorite group minerals and Hematite (Fe2O3)) — mineral

Phantom Quartz with Chlorite and Hematite inclusions

Silicon Dioxide (SiO2) with inclusions of Chlorite group minerals and Hematite (Fe2O3)

Bloodstone (Heliotrope) (Chalcedony (SiO2) with inclusions of Iron Oxide or Red Jasper) — mineral

Bloodstone (Heliotrope)

Chalcedony (SiO2) with inclusions of Iron Oxide or Red Jasper

Azurite (Azurite (Cu3(CO3)2(OH)2)) — mineral

Azurite

Azurite (Cu3(CO3)2(OH)2)

Malachite (Copper carbonate hydroxide, Cu2CO3(OH)2) — mineral

Malachite

Copper carbonate hydroxide, Cu2CO3(OH)2

Yellow Quartzite (Iron-stained Quartz) (Silicon Dioxide (SiO2) with iron oxide staining) — metamorphic

Yellow Quartzite (Iron-stained Quartz)

Silicon Dioxide (SiO2) with iron oxide staining

Bornite (Bornite (Cu5FeS4)) — mineral

Bornite

Bornite (Cu5FeS4)

Red Quartzite (Quartzite (primarily SiO2 with hematite inclusions)) — metamorphic

Red Quartzite

Quartzite (primarily SiO2 with hematite inclusions)

Metallic Ornament / Jewelry (N/A - This is an artificial object, not a geological specimen.) — This appears to be a man-made metallic object, likely jewelry, not a natural rock, mineral, or geological specimen.

Metallic Ornament / Jewelry

N/A - This is an artificial object, not a geological specimen.

This appears to be a man-made metallic object, likely jewelry, not a natural rock, mineral, or geological specimen.

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Rhodonite (Manganese Silicate (Mn,Fe,Mg,Ca)SiO3) — mineral

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

Red Quartzite / Ferruginous Quartz (Quartzite (primarily Silicon Dioxide, SiO2 with Iron Oxide impurities)) — metamorphic

Red Quartzite / Ferruginous Quartz

Quartzite (primarily Silicon Dioxide, SiO2 with Iron Oxide impurities)

Emerald (Beryl (Be3Al2(SiO3)6) with Chromium and/or Vanadium impurities) — mineral

Emerald

Beryl (Be3Al2(SiO3)6) with Chromium and/or Vanadium impurities

Zebra Jasper (Silicon Dioxide (SiO2) with iron oxide and manganese inclusions) — metamorphic

Zebra Jasper

Silicon Dioxide (SiO2) with iron oxide and manganese inclusions

Quartzite (Iron-stained) (Quartzite (mostly SiO2)) — metamorphic

Quartzite (Iron-stained)

Quartzite (mostly SiO2)

Rough Diamond (Diamond (pure Carbon, C)) — mineral

Rough Diamond

Diamond (pure Carbon, C)

Ferruginous Quartz (Silicon Dioxide (SiO2) with Iron Oxide inclusions (Hematite/Goethite)) — mineral

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide inclusions (Hematite/Goethite)

Quartzite (or Ferruginous Quartz) (Silicon Dioxide (SiO2) with Iron Oxide inclusions) — metamorphic

Quartzite (or Ferruginous Quartz)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Green Aventurine (Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)) — metamorphic

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)

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

Quartz (Rose/Milky variety)

Silicon Dioxide (SiO2)

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

Peridot

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

Red Quartzite (Quartzite (SiO2 with iron oxide impurities)) — metamorphic

Red Quartzite

Quartzite (SiO2 with iron oxide impurities)

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese