Rock Identifier

Category

Sedimentary (Chemically Precipitated)

Browse sedimentary (chemically precipitated) specimens identified by the Rock Identifier community.

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

Quartz (Rock Crystal)

Quartz (SiO₂ - Silicon Dioxide)

Mineral
Quartz (Quartz (SiO₂)) — Mineral

Quartz

Quartz (SiO₂)

Mineral
Limestone (Calcareous Sedimentary Rock (CaCO3)) — sedimentary

Limestone

Calcareous Sedimentary Rock (CaCO3)

sedimentary
Limestone (Calcareous sedimentary rock (CaCO3)) — sedimentary

Limestone

Calcareous sedimentary rock (CaCO3)

sedimentary
Conglomerate (Conglomerate (clastic sedimentary rock)) — sedimentary

Conglomerate

Conglomerate (clastic sedimentary rock)

sedimentary
Concretion or Geode (unbroken) (Varied (depending on mineral composition and cementing agent). For quartz-lined geodes, the scientific name of the dominant mineral would be Quartz (SiO2). For calcite-lined geodes, Calcite (CaCO3). Concretions are often composed of cryptocrystalline quartz (chert), calcite, or iron oxides.) — Sedimentary rock (specifically a concretion or possibly a geode)

Concretion or Geode (unbroken)

Varied (depending on mineral composition and cementing agent). For quartz-lined geodes, the scientific name of the dominant mineral would be Quartz (SiO2). For calcite-lined geodes, Calcite (CaCO3). Concretions are often composed of cryptocrystalline quartz (chert), calcite, or iron oxides.

Sedimentary rock (specifically a concretion or possibly a geode)
Graphite (Graphite (Native Carbon, C)) — metamorphic

Graphite

Graphite (Native Carbon, C)

metamorphic
Mookaite (Mookaite Jasper) (Silicified Radiolarite (SiO2 with iron oxides)) — sedimentary

Mookaite (Mookaite Jasper)

Silicified Radiolarite (SiO2 with iron oxides)

sedimentary
Chert (Iron-stained) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

sedimentary
Red Jasper (Opaque Chalcedony) (Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions) — sedimentary

Red Jasper (Opaque Chalcedony)

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

sedimentary
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx') (Calcite (CaCO3)) — sedimentary

Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')

Calcite (CaCO3)

sedimentary
Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

sedimentary
Chert (varietal Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (varietal Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

sedimentary
Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

sedimentary
Chert (Iron-stained) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

sedimentary
Chert (Jasper/Flint variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

sedimentary
Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

sedimentary
Hag Stone (Calcareous sedimentary rock (often Chert, Flint, or Limestone)) — sedimentary

Hag Stone

Calcareous sedimentary rock (often Chert, Flint, or Limestone)

sedimentary
Yellow Chert or Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Yellow Chert or Jasper

Microcrystalline Quartz (SiO2)

sedimentary
Blue Apatite (Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

mineral
Agate (Chalcedony) (Cryptocrystalline Silica or Silicon Dioxide (SiO2)) — mineral

Agate (Chalcedony)

Cryptocrystalline Silica or Silicon Dioxide (SiO2)

mineral
Chert Nodule (River Cobble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert Nodule (River Cobble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

sedimentary
Sandstone (Sandstone (lithified sand)) — sedimentary

Sandstone

Sandstone (lithified sand)

sedimentary
Epidote (or Epidote-rich rock) (Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).) — Mineral, often found in metamorphic rocks but also in sedimentary and igneous rocks

Epidote (or Epidote-rich rock)

Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).

Mineral, often found in metamorphic rocks but also in sedimentary and igneous rocks
Yellow Chalcedony (Agate/Carnelian variant) (Silicon Dioxide (SiO₂)) — mineral

Yellow Chalcedony (Agate/Carnelian variant)

Silicon Dioxide (SiO₂)

mineral
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)

Sedimentary
Dolomite (Dolomite (CaMg(CO3)2)) — Mineral

Dolomite

Dolomite (CaMg(CO3)2)

Mineral
Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

sedimentary
Fluorite Octahedron (Fluorite (Calcium Fluoride, CaF2)) — mineral

Fluorite Octahedron

Fluorite (Calcium Fluoride, CaF2)

mineral
Crushed Limestone (Sedimentary Carbonate Rock (CaCO3)) — sedimentary

Crushed Limestone

Sedimentary Carbonate Rock (CaCO3)

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

Chert (variations include Flint or Jasper)

Silicon Dioxide (SiO2)

sedimentary
Chert (Black Chert/Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Black Chert/Flint)

Silicon Dioxide (SiO2)

sedimentary
Banded Chert (Ironstone/Jasper) (Cryptocrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Banded Chert (Ironstone/Jasper)

Cryptocrystalline Quartz (SiO2) with Iron Oxides

sedimentary
Chert (Chert / Flint nodule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Chert / Flint nodule)

Silicon Dioxide (SiO2)

sedimentary
Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

sedimentary
Chert (Brecciated or Veined) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Brecciated or Veined)

Silicon Dioxide (SiO2)

sedimentary
Limestone (CaCO3 (principally composed of Calcite)) — sedimentary

Limestone

CaCO3 (principally composed of Calcite)

sedimentary
Quartz (Smoky/Milky variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Smoky/Milky variety)

Silicon Dioxide (SiO2)

mineral
Chert (Hag Stone / Hole Stone) (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert (Hag Stone / Hole Stone)

Chert (Cryptocrystalline variety of Quartz, SiO2)

sedimentary
Glauconitic Sandstone (or Greensand) (Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone (or Greensand)

Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)

sedimentary
Banded Chert (Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Banded Chert (Jasper)

Silicon Dioxide (SiO2)

sedimentary
Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

sedimentary