Rock Identifier

Category

Sedimentary (Secondary Formation)

Browse sedimentary (secondary formation) specimens identified by the Rock Identifier community.

Banded Slate or Siltstone with Quartz/Calcite Veins (Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)) — metamorphic

Banded Slate or Siltstone with Quartz/Calcite Veins

Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)

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

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Chalcedony (Chalcedony (SiO2)) — mineral

Chalcedony

Chalcedony (SiO2)

Limestone with Calcite Veins (Calcium Carbonate (CaCO3) - Sparry Limestone) — sedimentary

Limestone with Calcite Veins

Calcium Carbonate (CaCO3) - Sparry Limestone

Native Sulfur (Sulfur (S)) — mineral

Native Sulfur

Sulfur (S)

Pyrite on Quartz matrix (Iron Disulfide (FeS2) on Silicon Dioxide (SiO2)) — mineral

Pyrite on Quartz matrix

Iron Disulfide (FeS2) on Silicon Dioxide (SiO2)

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

Optical Calcite

Calcite (Calcium Carbonate, CaCO3)

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

Yellow Agate

Silicon Dioxide (SiO2) - variety of Chalcedony

Limonite or Ironstone Nodule (Hydrated iron oxide-hydroxide (FeO(OH)·nH2O)) — mineral

Limonite or Ironstone Nodule

Hydrated iron oxide-hydroxide (FeO(OH)·nH2O)

Limonite Nodule (FeO(OH)·nH2O (Hydrated iron oxide-hydroxide)) — mineral

Limonite Nodule

FeO(OH)·nH2O (Hydrated iron oxide-hydroxide)

Limonite Nodules / Goethite (Hydrated Iron Oxide-Hydroxide (FeO(OH)·nH2O / Fe2O3·nH2O)) — mineral

Limonite Nodules / Goethite

Hydrated Iron Oxide-Hydroxide (FeO(OH)·nH2O / Fe2O3·nH2O)

Sandstone (Ferruginous) (Arenite (composed primarily of SiO2 with Fe2O3 staining)) — sedimentary

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 staining)

Banded Agate (Chalcedony (Silicon Dioxide, SiO2)) — mineral

Banded Agate

Chalcedony (Silicon Dioxide, SiO2)

Brown Agate (Cryptocrystalline Silica (SiO2)) — sedimentary

Brown Agate

Cryptocrystalline Silica (SiO2)

Banded Agate (specifically Carnelian Agate) (Silicon Dioxide (SiO2)) — mineral

Banded Agate (specifically Carnelian Agate)

Silicon Dioxide (SiO2)

Agate (Silicon dioxide (SiO2)) — mineral

Agate

Silicon dioxide (SiO2)

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

Brecciated Jasper

Silicon Dioxide (SiO2) with iron impurities

Calcite with iron staining (Calcium Carbonate (CaCO3)) — mineral

Calcite with iron staining

Calcium Carbonate (CaCO3)

Siltstone with Fossil Cast (Sedimentary Rock (Siltstone / Fine-grained Sandstone)) — sedimentary

Siltstone with Fossil Cast

Sedimentary Rock (Siltstone / Fine-grained Sandstone)

Honey Calcite (Calcium Carbonate (CaCO3)) — mineral

Honey Calcite

Calcium Carbonate (CaCO3)

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

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Green Calcite (Calcium Carbonate (CaCO3)) — mineral

Green Calcite

Calcium Carbonate (CaCO3)

Sandstone with Secondary Mineral Encrustation (Arenite with Silica/Calcite deposits (SiO2 or CaCO3)) — sedimentary

Sandstone with Secondary Mineral Encrustation

Arenite with Silica/Calcite deposits (SiO2 or CaCO3)

Banded Agate (Silicon Dioxide (SiO2) - Chalcedony) — sedimentary

Banded Agate

Silicon Dioxide (SiO2) - Chalcedony

Agate (translucent water-worn pebble) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Agate (translucent water-worn pebble)

Cryptocrystalline Quartz (SiO2)

Green Calcite (Calcium Carbonate (CaCO3)) — mineral

Green Calcite

Calcium Carbonate (CaCO3)

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

Agate

Agate (Silicon Dioxide, SiO2)

Specular Hematite (Specularite) (Iron Oxide (Fe2O3)) — mineral

Specular Hematite (Specularite)

Iron Oxide (Fe2O3)

Carnelian (SiO2 (Silicon Dioxide) - Translucent Chalcedony) — mineral

Carnelian

SiO2 (Silicon Dioxide) - Translucent Chalcedony

Yellow Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Limonite (Goethite/Ironstone) (Hydrated iron oxide-hydroxide, approximately FeO(OH)·nH2O) — mineral

Limonite (Goethite/Ironstone)

Hydrated iron oxide-hydroxide, approximately FeO(OH)·nH2O

Quartz (Clear to Smokey) (Silicon Dioxide (SiO2)) — mineral

Quartz (Clear to Smokey)

Silicon Dioxide (SiO2)

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Chert (Iron-stained) (Chert (SiO2)) — sedimentary

Chert (Iron-stained)

Chert (SiO2)

Quartz (Jasper / Chert) (Silicon Dioxide (SiO2)) — sedimentary

Quartz (Jasper / Chert)

Silicon Dioxide (SiO2)

Limonite with Trace Fossils (Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)) — sedimentary

Limonite with Trace Fossils

Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)

Limonite / Ironstone Nodule (Hydrated Iron Oxide (FeO(OH)·nH2O)) — sedimentary

Limonite / Ironstone Nodule

Hydrated Iron Oxide (FeO(OH)·nH2O)

Ferruginous Quartz (Silicon Dioxide with Hematite/Limonite inclusions (SiO2 + Fe2O3)) — mineral

Ferruginous Quartz

Silicon Dioxide with Hematite/Limonite inclusions (SiO2 + Fe2O3)

Hematite (Iron Ore) (Hematite (Fe2O3)) — mineral

Hematite (Iron Ore)

Hematite (Fe2O3)

Ironstone Concretion / Goethite-Hematite Nodule (Goethite/Hematite (α-FeO(OH) / Fe2O3)) — sedimentary

Ironstone Concretion / Goethite-Hematite Nodule

Goethite/Hematite (α-FeO(OH) / Fe2O3)

Jasper with Quartz Veining (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper with Quartz Veining

Silicon Dioxide (SiO2) with iron oxide inclusions

Quartz Geode (partially opened) (Silicon Dioxide (SiO2) with iron staining) — mineral

Quartz Geode (partially opened)

Silicon Dioxide (SiO2) with iron staining