Rock Identifier

Category

Mineral, Often Found As Detrital Grains In Sedimentary Rocks

Browse mineral, often found as detrital grains in sedimentary rocks specimens identified by the Rock Identifier community.

Yellow Chalcedony (common opal or chert variant) (Silicon Dioxide (SiO2)) — sedimentary (mineraloid/microcrystalline quartz)

Yellow Chalcedony (common opal or chert variant)

Silicon Dioxide (SiO2)

sedimentary (mineraloid/microcrystalline quartz)

Carnelian Agate (Chalcedony (SiO2) with iron oxide inclusions) — mineral

Carnelian Agate

Chalcedony (SiO2) with iron oxide inclusions

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

Quartz Vein / Milky Quartz

Silicon Dioxide (SiO2)

Quartzite (Quartzite (chiefly SiO2)) — metamorphic

Quartzite

Quartzite (chiefly SiO2)

Granite (Granite (a plutonic igneous rock)) — Igneous

Granite

Granite (a plutonic igneous rock)

Schist (Schist (various mineral compositions)) — metamorphic

Schist

Schist (various mineral compositions)

Celestine (Celestite) (Strontium Sulfate (SrSO4)) — mineral

Celestine (Celestite)

Strontium Sulfate (SrSO4)

Celestite (Celestine) (Strontium sulfate (SrSO4)) — mineral

Celestite (Celestine)

Strontium sulfate (SrSO4)

Granite (Granite (High-silica plutonic rock)) — Igneous

Granite

Granite (High-silica plutonic rock)

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

Quartz / Rock Crystal

Silicon Dioxide (SiO2)

Granitic Gneiss (Gneiss (Metamorphic Rock)) — metamorphic

Granitic Gneiss

Gneiss (Metamorphic Rock)

Sandstone (Arenite (SiO2 primarily)) — sedimentary

Sandstone

Arenite (SiO2 primarily)

Pyrite (on the right) and Magnetite or Hematite (on the left) (Iron Sulfide (FeS2) and Iron Oxide (Fe3O4 or Fe2O3)) — mineral

Pyrite (on the right) and Magnetite or Hematite (on the left)

Iron Sulfide (FeS2) and Iron Oxide (Fe3O4 or Fe2O3)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Ironstone Concretion (Limonite/Goethite) (Goethite-rich Concretion (FeO(OH))) — sedimentary

Ironstone Concretion (Limonite/Goethite)

Goethite-rich Concretion (FeO(OH))

Nephrite Jade (Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)) — Mineral

Nephrite Jade

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)

Granite (Granite (Mainly Quartz, Feldspar, and Mica/Amphibole)) — igneous

Granite

Granite (Mainly Quartz, Feldspar, and Mica/Amphibole)

Gneiss (Pebble) (Gneiss) — metamorphic

Gneiss (Pebble)

Gneiss

Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

Geode (Chert or Quartz Nodule) (Silicon Dioxide (SiO2)) — sedimentary

Geode (Chert or Quartz Nodule)

Silicon Dioxide (SiO2)

Carnelian (Carnelian (Cryptocrystalline Quartz, SiO2)) — mineral

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

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

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Chert or Flint (polished/water-worn) (Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.) — Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)

Chert or Flint (polished/water-worn)

Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.

Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)

Quartzite (River Stone) (Quartzite (mainly SiO2 with iron oxide staining)) — metamorphic

Quartzite (River Stone)

Quartzite (mainly SiO2 with iron oxide staining)

Rhodonite with Manganese Oxides (Rhodonite (Mn,Fe,Mg,Ca)SiO3) — metamorphic

Rhodonite with Manganese Oxides

Rhodonite (Mn,Fe,Mg,Ca)SiO3

Apatite (Apatite Group (e.g., Fluorapatite Ca5(PO4)3F, Chlorapatite Ca5(PO4)3Cl, Hydroxylapatite Ca5(PO4)3(OH))) — mineral

Apatite

Apatite Group (e.g., Fluorapatite Ca5(PO4)3F, Chlorapatite Ca5(PO4)3Cl, Hydroxylapatite Ca5(PO4)3(OH))

Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Quartzite (SiO2)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Red Jasper (beads) (Silicon Dioxide (SiO2) with iron inclusions) — Sedimentary Rock

Red Jasper (beads)

Silicon Dioxide (SiO2) with iron inclusions

Sedimentary Rock

Pegmatite (likely Granitic Pegmatite) (Pegmatite (a coarse-grained igneous rock, often with granitic composition)) — igneous

Pegmatite (likely Granitic Pegmatite)

Pegmatite (a coarse-grained igneous rock, often with granitic composition)

Schist (Mica Schist) — metamorphic

Schist

Mica Schist

Fluorite (Fluorite (Calcium Fluoride, CaF2)) — Mineral

Fluorite

Fluorite (Calcium Fluoride, CaF2)

Conglomerate (Conglomerate (Clastic Sedimentary Rock)) — sedimentary

Conglomerate

Conglomerate (Clastic Sedimentary Rock)

Quartz Vein in River Siltstone (Crystalline Quartz (SiO2) in Siliclastic Matrix) — sedimentary

Quartz Vein in River Siltstone

Crystalline Quartz (SiO2) in Siliclastic Matrix

Honey Calcite Geode Segment (Calcite (Calcium Carbonate, CaCO3)) — mineral

Honey Calcite Geode Segment

Calcite (Calcium Carbonate, CaCO3)

Biotite Schist (Biotite Mica Schist [K(Mg,Fe)3AlSi3O10(OH,F)2]) — metamorphic

Biotite Schist

Biotite Mica Schist [K(Mg,Fe)3AlSi3O10(OH,F)2]

Banded Agate (Jasper-Agate) (Silicon Dioxide (SiO₂)) — Mineral

Banded Agate (Jasper-Agate)

Silicon Dioxide (SiO₂)

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

Carnelian Agate

Silicon Dioxide (SiO2) - variety of Chalcedony

Celestite (Celestine) (Strontium sulfate (SrSO4)) — mineral

Celestite (Celestine)

Strontium sulfate (SrSO4)

Yellow Quartzite (Quartzite (primarily SiO2)) — metamorphic

Yellow Quartzite

Quartzite (primarily SiO2)

Slate (Foliated Metamorphic Rock (Mainly composed of Quartz, Illite, Chlorite)) — metamorphic

Slate

Foliated Metamorphic Rock (Mainly composed of Quartz, Illite, Chlorite)