Rock Identifier

Category

Mineral, Specifically A Rock Fragment

Browse mineral, specifically a rock fragment specimens identified by the Rock Identifier community.

Pyrite on Limestone (Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix) — sedimentary (matrix) / mineral (inclusion)

Pyrite on Limestone

Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix

sedimentary (matrix) / mineral (inclusion)

Druzy Quartz on Limestone (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz on Limestone

Silicon Dioxide (SiO2)

Granite (Granite (a plutonic rock)) — Igneous

Granite

Granite (a plutonic rock)

Biotite Schist (Biotite Schist (Rich in K(Mg,Fe)3AlSi3O10(OH)2)) — metamorphic

Biotite Schist

Biotite Schist (Rich in K(Mg,Fe)3AlSi3O10(OH)2)

Limestone with Fossil inclusions (Fossiliferous Limestone (CaCO3)) — sedimentary

Limestone with Fossil inclusions

Fossiliferous Limestone (CaCO3)

Chert (specifically Gray/Black Chert) (Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (specifically Gray/Black Chert)

Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)

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.

Unable to Identify (Image Obscured) — Indeterminate

Unable to Identify (Image Obscured)

River Rock (likely Siltstone or fine-grained Sandstone) (Clastic Sedimentary Rock) — sedimentary

River Rock (likely Siltstone or fine-grained Sandstone)

Clastic Sedimentary Rock

Note regarding image quality — Indeterminate

Note regarding image quality

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Honeycomb Coral Fossil (Petoskey-type Coral) (Favosites (Extinct Colonial Tabulate Coral), CaCO3) — sedimentary

Honeycomb Coral Fossil (Petoskey-type Coral)

Favosites (Extinct Colonial Tabulate Coral), CaCO3

Siltstone (Siltstone (primarily composed of SiO2)) — sedimentary

Siltstone

Siltstone (primarily composed of SiO2)

Quartz (River Pebble) (Silicon Dioxide (SiO2)) — mineral

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Quartz in Basalt (Xenocryst) (Silicon Dioxide (SiO2) in Mafic Igneous Volcanic Rock) — Igneous

Quartz in Basalt (Xenocryst)

Silicon Dioxide (SiO2) in Mafic Igneous Volcanic Rock

Quartz (Rock Crystal) with minor impurities (Quartz (SiO2)) — Mineral

Quartz (Rock Crystal) with minor impurities

Quartz (SiO2)

Petrified Dinosaur Bone (Gembone) (Agatized Dinosaur Bone) — sedimentary

Petrified Dinosaur Bone (Gembone)

Agatized Dinosaur Bone

Amethyst (Amethyst (Silicon Dioxide, SiO2)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Quartz-veined Basalt (Amygdaloidal or Porphyritic Basalt with Silicon Dioxide (SiO2) vein) — igneous

Quartz-veined Basalt

Amygdaloidal or Porphyritic Basalt with Silicon Dioxide (SiO2) vein

Quartz Vein in Schist (Quartz (SiO2) in Mica Schist) — metamorphic

Quartz Vein in Schist

Quartz (SiO2) in Mica Schist

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

Limonite (Iron Ore)

Limonite (Hydrous iron(III) oxide-hydroxide mixture, primarily FeO(OH)·nH2O)

Limonite (Iron Ore) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Basalt with Quartz Veining (Basalt (Mafic Extrusive Igneous Rock) with SiO2 (Silicon Dioxide) veins) — igneous

Basalt with Quartz Veining

Basalt (Mafic Extrusive Igneous Rock) with SiO2 (Silicon Dioxide) veins

Black Limestone with Calcite Veining (Bituminous Limestone (CaCO3 with Organic Carbon inclusions)) — sedimentary

Black Limestone with Calcite Veining

Bituminous Limestone (CaCO3 with Organic Carbon inclusions)

Quartz-Veined Mudstone (Argillaceous Mudstone with Quartz Veining) — sedimentary

Quartz-Veined Mudstone

Argillaceous Mudstone with Quartz Veining

Chert (variant Flint or Jasper) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (variant Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fulgurite (Fulgurite (Lechatelierite-rich fused silica)) — mineraloid / sedimentary (secondary formation)

Fulgurite

Fulgurite (Lechatelierite-rich fused silica)

mineraloid / sedimentary (secondary formation)

Clear Quartz (Silicon dioxide (SiO2)) — mineral

Clear Quartz

Silicon dioxide (SiO2)

Lapis Lazuli (Tumbled) (Lazurite-dominated contact metamorphic rock) — metamorphic

Lapis Lazuli (Tumbled)

Lazurite-dominated contact metamorphic rock

Lapis Lazuli (Na8[Al6Si6O24]Sn (Lazurite-rich metamorphic rock)) — metamorphic

Lapis Lazuli

Na8[Al6Si6O24]Sn (Lazurite-rich metamorphic rock)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Sandstone (Arenite or Sandstone) — Sedimentary Rock

Sandstone

Arenite or Sandstone

Sedimentary Rock

Granite (Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Granite

Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)

Tiger's Eye (with Blue Tiger's Eye / Hawk's Eye) (Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)) — metamorphic

Tiger's Eye (with Blue Tiger's Eye / Hawk's Eye)

Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)

Onyx Marble (also commonly called Onyx) (Calcite (CaCO3), often with other mineral impurities) — Sedimentary Rock (specifically a type of Travertine)

Onyx Marble (also commonly called Onyx)

Calcite (CaCO3), often with other mineral impurities

Sedimentary Rock (specifically a type of Travertine)

Eclogite (Eclogite (Omphacite + Pyrope)) — metamorphic

Eclogite

Eclogite (Omphacite + Pyrope)

Quartz Geode (with possible Manganese or Goethite coating) (Silicon Dioxide (SiO2)) — mineral

Quartz Geode (with possible Manganese or Goethite coating)

Silicon Dioxide (SiO2)

Chert (Chert (microcrystalline quartz, SiO2)) — Sedimentary

Chert

Chert (microcrystalline quartz, SiO2)

Serpentinite (Serpentinite (composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite)) — metamorphic

Serpentinite

Serpentinite (composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite)

Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Bauxite (Bauxite (Al2O3·nH2O)) — sedimentary

Bauxite

Bauxite (Al2O3·nH2O)

Limonite-stained Quartz (Silicon Dioxide (SiO2) with Iron Oxide/Hydroxide (FeO(OH)·nH2O) staining) — mineral

Limonite-stained Quartz

Silicon Dioxide (SiO2) with Iron Oxide/Hydroxide (FeO(OH)·nH2O) staining