Rock Identifier

Category

Limestone

Browse limestone specimens identified by the Rock Identifier community.

Horn Coral Fossil (Rugosa (extinct order of solitary corals)) — sedimentary

Horn Coral Fossil

Rugosa (extinct order of solitary corals)

Travertine (Calcareous Tufa) (Calcium Carbonate (CaCO3)) — sedimentary

Travertine (Calcareous Tufa)

Calcium Carbonate (CaCO3)

Devil's Toenail (Gryphaea (extinct genus of foam oysters, typically composed of Calcite CaCO3)) — sedimentary

Devil's Toenail

Gryphaea (extinct genus of foam oysters, typically composed of Calcite CaCO3)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossiliferous Chert with Brachiopod Impression (Chert (SiO2) containing Brachiopoda fossil remains) — sedimentary

Fossiliferous Chert with Brachiopod Impression

Chert (SiO2) containing Brachiopoda fossil remains

Brachiopod Fossil (Spiriferid) (Order Spiriferida (Phylum Brachiopoda); mineralized as Calcite (CaCO3) or Chert (SiO2)) — sedimentary (fossilized organic remain)

Brachiopod Fossil (Spiriferid)

Order Spiriferida (Phylum Brachiopoda); mineralized as Calcite (CaCO3) or Chert (SiO2)

sedimentary (fossilized organic remain)

Chert (Nodule) (Silicon dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (Nodule)

Silicon dioxide (SiO2) - Cryptocrystalline Quartz

Chert (varietal: Flint/Jasper mix) (Hydrous Silica (SiO2)) — sedimentary

Chert (varietal: Flint/Jasper mix)

Hydrous Silica (SiO2)

Chert (Quartz Variety) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (Quartz Variety)

Microcrystalline Silica (SiO2)

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

Chert (variant Flint/Novaculite)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (varietal known as Jasper or Flint) (Silicon Dioxide (SiO2)) — Sedimentary Rock

Chert (varietal known as Jasper or Flint)

Silicon Dioxide (SiO2)

Sedimentary Rock

Chert (specifically Flint or Gray Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Gray Chert)

Silicon Dioxide (SiO2)

Chert (specifically Flint or Gray Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Gray Chalcedony)

Microcrystalline Quartz (SiO2)

Chert (varietal: Flint or River Pebble) (Silicon Dioxide (SiO₂)) — sedimentary

Chert (varietal: Flint or River Pebble)

Silicon Dioxide (SiO₂)

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (specifically Flint or Jasper variant)

Cryptocrystalline Quartz (SiO2)

Polygenetic Conglomerate (Puddingstone) (Conglomerate (SiO2 matrix with mixed clasts)) — sedimentary

Polygenetic Conglomerate (Puddingstone)

Conglomerate (SiO2 matrix with mixed clasts)

Coral Fossil (Favosites) (Favosites (Calcite/Calcium Carbonate, CaCO3)) — sedimentary

Coral Fossil (Favosites)

Favosites (Calcite/Calcium Carbonate, CaCO3)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Botryoidal Goethite on Quartz (Goethite (α-Fe3+O(OH)) on Quartz (SiO2)) — mineral

Botryoidal Goethite on Quartz

Goethite (α-Fe3+O(OH)) on Quartz (SiO2)

Chert (specifically Red Chert / Jasper nodule) (Silicon dioxide (SiO2)) — sedimentary

Chert (specifically Red Chert / Jasper nodule)

Silicon dioxide (SiO2)

Botryoidal Chalcedony (likely Chert or Agatized Coral) (Silicon Dioxide (SiO2)) — mineral

Botryoidal Chalcedony (likely Chert or Agatized Coral)

Silicon Dioxide (SiO2)

Chert (often called Flint when dark) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (and Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Druzy Quartz on Matrix

Silicon Dioxide (SiO2)

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

Chert (Black Chert/Flint)

Silicon Dioxide (SiO2)

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

Chert (Red Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (variations include Flint) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (variations include Flint)

Chert (Silicon Dioxide, SiO2)

Brachiopod Fossil in Chert (Phylum Brachiopoda within Microcrystalline Quartz (SiO2)) — sedimentary

Brachiopod Fossil in Chert

Phylum Brachiopoda within Microcrystalline Quartz (SiO2)

Azurite and Malachite on Matrix (Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2) — mineral

Azurite and Malachite on Matrix

Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Quartzite Pebble (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Chert (Flint variety) (Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2) — sedimentary

Chert (Flint variety)

Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2

Chert (with small quartz inclusion) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (with small quartz inclusion)

Microcrystalline Silica (SiO2)

Quartz Geode (Crystalline Silicon Dioxide (SiO2) within a nodule) — sedimentary

Quartz Geode

Crystalline Silicon Dioxide (SiO2) within a nodule

Lapis Lazuli (prominent blue specimen in collection) (Lazurite-rich metamorphic rock (Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2) — metamorphic

Lapis Lazuli (prominent blue specimen in collection)

Lazurite-rich metamorphic rock (Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2

Charoite ((K,Sr,Ba,Ca)15-16(Na,Ca)8(Si,Al)24O60(OH,F)4 · nH2O (Hydrated silicate of potassium, calcium, and sodium)) — metamorphic

Charoite

(K,Sr,Ba,Ca)15-16(Na,Ca)8(Si,Al)24O60(OH,F)4 · nH2O (Hydrated silicate of potassium, calcium, and sodium)

Chert (Nodular or Fossiliferous) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Nodular or Fossiliferous)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Jasper variety) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)