Rock Identifier

Category

Mineral (Sedimentary Context)

Browse mineral (sedimentary context) specimens identified by the Rock Identifier community.

Learn about Mineral (Sedimentary Context) in the encyclopedia

Coal

Claystone

Shale

Marl

Black Shale

Likely quartz-rich stone (possibly milky quartz or quartzite) (Quartz, silicon dioxide (SiO₂), or quartzite if interlocking grains are present) — mineral

Likely quartz-rich stone (possibly milky quartz or quartzite)

Quartz, silicon dioxide (SiO₂), or quartzite if interlocking grains are present

Milky quartz fragment (Quartz (silicon dioxide, SiO₂)) — mineral

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Milky quartz (likely quartz vein fragment) (Quartz, silicon dioxide (SiO₂)) — mineral

Milky quartz (likely quartz vein fragment)

Quartz, silicon dioxide (SiO₂)

Angelite (Blue Anhydrite) (Anhydrite (CaSO4)) — mineral

Angelite (Blue Anhydrite)

Anhydrite (CaSO4)

Sandstone with Iron Staining (Arenite (SiO2 with Fe-oxide coatings)) — sedimentary

Sandstone with Iron Staining

Arenite (SiO2 with Fe-oxide coatings)

Rhodochrosite (Manganese Carbonate (MnCO3)) — mineral

Rhodochrosite

Manganese Carbonate (MnCO3)

Fossil Shell (Bivalve) (Class Bivalvia (fossilized)) — fossil

Fossil Shell (Bivalve)

Class Bivalvia (fossilized)

Green Jasper (Silicon Dioxide (SiO2) with impurities) — sedimentary

Green Jasper

Silicon Dioxide (SiO2) with impurities

Sandstone (Sedimentary Rock (Quartz Sandstone)) — sedimentary

Sandstone

Sedimentary Rock (Quartz Sandstone)

Limonite Concretion (Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)wnH2O)) — sedimentary

Limonite Concretion

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)wnH2O)

Jasper (Silicon Dioxide (SiO2) with iron oxide impurities) — sedimentary

Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Sandstone (Quartz-rich) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartz-rich)

Arenite (primarily SiO2)

Likely ironstone pebble (Iron-rich concretion, probably goethite/limonite cementing sediment; exact identification is uncertain from the photograph) — sedimentary

Likely ironstone pebble

Iron-rich concretion, probably goethite/limonite cementing sediment; exact identification is uncertain from the photograph

Banded gneiss (Gneiss; typically quartz–feldspar–biotite ± amphibole) — metamorphic

Banded gneiss

Gneiss; typically quartz–feldspar–biotite ± amphibole

Likely weathered granite or granitic gneiss fragments (Granite: quartz–feldspar–mica aggregate; possibly biotite granite or weakly foliated gneiss) — igneous

Likely weathered granite or granitic gneiss fragments

Granite: quartz–feldspar–mica aggregate; possibly biotite granite or weakly foliated gneiss

Sea Shell Fragment (Calcium Carbonate) (Aragonite / Calcite (CaCO3)) — mineral

Sea Shell Fragment (Calcium Carbonate)

Aragonite / Calcite (CaCO3)

Layered shale or mudstone fragment (Fissile claystone/mudstone, commonly clay minerals with quartz and minor iron oxides) — sedimentary

Layered shale or mudstone fragment

Fissile claystone/mudstone, commonly clay minerals with quartz and minor iron oxides

Vesicular basalt (likely amygdaloidal basalt) (Basalt, a mafic volcanic rock composed mainly of plagioclase feldspar, clinopyroxene, and commonly olivine; vesicles are partly mineral-filled amygdules.) — igneous

Vesicular basalt (likely amygdaloidal basalt)

Basalt, a mafic volcanic rock composed mainly of plagioclase feldspar, clinopyroxene, and commonly olivine; vesicles are partly mineral-filled amygdules.

Agate Geode (Silicon Dioxide (SiO2) - Chalcedony variety) — sedimentary

Agate Geode

Silicon Dioxide (SiO2) - Chalcedony variety

Fern fossil in shale (Plant fossil, likely a fern frond impression preserved in fine-grained shale; exact species indeterminable from the image) — fossil

Fern fossil in shale

Plant fossil, likely a fern frond impression preserved in fine-grained shale; exact species indeterminable from the image

Green Fluorite (Calcium Fluoride (CaF2)) — mineral

Green Fluorite

Calcium Fluoride (CaF2)

Blue Apatite (Fluorapatite (Ca5(PO4)3F)) — mineral

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

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

Quartz Geode

Quartz (Silicon Dioxide, SiO2)

Chalcopyrite (Copper Iron Sulfide (CuFeS2)) — mineral

Chalcopyrite

Copper Iron Sulfide (CuFeS2)

Quartz-rich feldspathic rock, possibly granite or arkose (Granite-like aggregate of quartz (SiO₂), feldspar, and minor iron oxides) — igneous

Quartz-rich feldspathic rock, possibly granite or arkose

Granite-like aggregate of quartz (SiO₂), feldspar, and minor iron oxides

River Pebble (Quartzo-feldspathic rock fragment) — sedimentary

River Pebble

Quartzo-feldspathic rock fragment

Ironstone Nodules (Iron Concretion) (Siderite or Hematite Concretion) — sedimentary

Ironstone Nodules (Iron Concretion)

Siderite or Hematite Concretion

Graphite (Graphite (Carbon, C)) — mineral

Graphite

Graphite (Carbon, C)

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

River Pebble (Siltstone / Sandstone Pebble) (Sedimentary Rock (Quartz, Feldspar, Clay Minerals)) — sedimentary

River Pebble (Siltstone / Sandstone Pebble)

Sedimentary Rock (Quartz, Feldspar, Clay Minerals)

Marble (Metamorphosed Limestone (CaCO3)) — metamorphic

Marble

Metamorphosed Limestone (CaCO3)

Magnetite / Hematite (Iron Ore) (Magnetite (Fe3O4) or Hematite (Fe2O3)) — mineral

Magnetite / Hematite (Iron Ore)

Magnetite (Fe3O4) or Hematite (Fe2O3)

Limonite (FeO(OH)·nH2O) — mineral

Limonite

FeO(OH)·nH2O

Iron-rich sulfide ore (likely pyrite-bearing rock) (Likely pyrite (FeS₂) with dark host rock; exact identification is uncertain from the image alone.) — mineral

Iron-rich sulfide ore (likely pyrite-bearing rock)

Likely pyrite (FeS₂) with dark host rock; exact identification is uncertain from the image alone.

Tumbled yellow calcite (Calcite (CaCO₃)) — mineral

Tumbled yellow calcite

Calcite (CaCO₃)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Satin Spar (often marketed as Selenite) (Gypsum (CaSO4·2H2O)) — mineral

Satin Spar (often marketed as Selenite)

Gypsum (CaSO4·2H2O)

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Clear Calcite (Calcite (Calcium Carbonate, CaCO3)) — mineral

Clear Calcite

Calcite (Calcium Carbonate, CaCO3)

Agate (Silicon Dioxide (SiO2)) — mineral

Agate

Silicon Dioxide (SiO2)