Rock Identifier

Category

Sedimentary (Secondary Formation)

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

Banded Iron Formation (BIF) with Quartz (Banded Iron Formation, often composed of alternating layers of hematite (Fe2O3) or magnetite (Fe3O4) and chert (microcrystalline quartz, SiO2)) — Sedimentary

Banded Iron Formation (BIF) with Quartz

Banded Iron Formation, often composed of alternating layers of hematite (Fe2O3) or magnetite (Fe3O4) and chert (microcrystalline quartz, SiO2)

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

Limonite (Gozzany Iron)

Limonite (FeO(OH)·nH2O)

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

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Fluorite Tower (Fluorite (Calcium Fluoride - CaF2)) — mineral

Fluorite Tower

Fluorite (Calcium Fluoride - CaF2)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Blue Agate (Dyed) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — mineral

Blue Agate (Dyed)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Ferruginous Quartz (Silicon Dioxide (SiO2) with Iron Oxide inclusions) — mineral

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Seashell (Calcium Carbonate) (Calcium Carbonate (CaCO3)) — mineral

Seashell (Calcium Carbonate)

Calcium Carbonate (CaCO3)

Chert (Jasper / Petrified Wood) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper / Petrified Wood)

Microcrystalline Quartz (SiO2)

Fluorite (Calcium fluoride (CaF2)) — mineral

Fluorite

Calcium fluoride (CaF2)

K2 Stone (or K2 Jasper) (Azurite-in-Granite (Potassium Feldspar, Quartz, Plagioclase, Muscovite, and Azurite)) — igneous

K2 Stone (or K2 Jasper)

Azurite-in-Granite (Potassium Feldspar, Quartz, Plagioclase, Muscovite, and Azurite)

Diamond Druzy (Crystalline Diamond) (Carbon (C)) — mineral

Diamond Druzy (Crystalline Diamond)

Carbon (C)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Iron-stained Quartz (Silicon Dioxide (SiO2) with Hematite/Limonite impurities) — mineral

Iron-stained Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Agate (Grey Agate Slice) (Microcrystalline Quartz (SiO2)) — mineral

Agate (Grey Agate Slice)

Microcrystalline Quartz (SiO2)

Chert (with Quartz veins) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Quartz veins)

Microcrystalline Quartz (SiO2)

Sulfur (Native Sulfur (S8)) — mineral

Sulfur

Native Sulfur (S8)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Blue-green mineral specimen, likely chrysocolla or turquoise (Chrysocolla: hydrated copper phyllosilicate, approximately Cu₂H₂O₅Si; Turquoise: CuAl₆(PO₄)₄(OH)₈·4H₂O) — mineral

Blue-green mineral specimen, likely chrysocolla or turquoise

Chrysocolla: hydrated copper phyllosilicate, approximately Cu₂H₂O₅Si; Turquoise: CuAl₆(PO₄)₄(OH)₈·4H₂O

Quartzite with Hematite staining (Quartzite (SiO2) with iron oxide inclusions) — metamorphic

Quartzite with Hematite staining

Quartzite (SiO2) with iron oxide inclusions

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

Carnelian Agate

Chalcedony (Silicon Dioxide, SiO2)

Calcite (Calcite (CaCO₃, Calcium Carbonate)) — Mineral

Calcite

Calcite (CaCO₃, Calcium Carbonate)

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

Banded Chert (Jasper)

Silicon Dioxide (SiO2)

Diamond (Carbon (C)) — gemstone

Diamond

Carbon (C)

Sandstone with Liesegang Rings (Arenite with secondary Iron oxide (Limonite/Goethite) precipitation) — sedimentary

Sandstone with Liesegang Rings

Arenite with secondary Iron oxide (Limonite/Goethite) precipitation

Geode with Iron-Stained Quartz/Calcite (Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix) — sedimentary

Geode with Iron-Stained Quartz/Calcite

Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix

Carnelian (SiO2 (Silicon Dioxide, variety of Chalcedony)) — mineral

Carnelian

SiO2 (Silicon Dioxide, variety of Chalcedony)

Blue Lace Agate (Microcrystalline Quartz (Chalcedony), SiO2) — mineral

Blue Lace Agate

Microcrystalline Quartz (Chalcedony), SiO2

Quartz with Iron Staining (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Quartz with Iron Staining

Silicon Dioxide (SiO2) with iron oxide impurities

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Psilomelane (Black Hematite/Manganese Ore) (Barium Manganese Oxide (Formula: BaMn9O18(OH)4)) — mineral

Psilomelane (Black Hematite/Manganese Ore)

Barium Manganese Oxide (Formula: BaMn9O18(OH)4)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Ferruginous Quartz (Iron-stained Quartz) (Silicon Dioxide (SiO2) with Hematite/Limonite impurities) — mineral

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Chert (Jasper/Agate variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Agate variety)

Microcrystalline quartz (SiO2)

Chert / Flint (with quartz or calcite inclusion) (Silicon dioxide (SiO2)) — sedimentary

Chert / Flint (with quartz or calcite inclusion)

Silicon dioxide (SiO2)

Limonite (Iron-rich Siltstone / Sandstone base) (Hydrous ferric oxide mixture (FeO(OH)·nH2O)) — sedimentary

Limonite (Iron-rich Siltstone / Sandstone base)

Hydrous ferric oxide mixture (FeO(OH)·nH2O)

Conglomerate Pebble (with Chert / Quartz) (Sedimentary Conglomerate / Breccia Pebble) — sedimentary

Conglomerate Pebble (with Chert / Quartz)

Sedimentary Conglomerate / Breccia Pebble

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

Chert (Jasper / Flint variant)

Microcrystalline Quartz (SiO2)

Quartz crystal cluster (Quartz, silicon dioxide (SiO₂), likely milky or partially included rock crystal) — mineral

Quartz crystal cluster

Quartz, silicon dioxide (SiO₂), likely milky or partially included rock crystal

Chert (with Quartz Vein) (Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)) — sedimentary

Chert (with Quartz Vein)

Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)

Specular Hematite (Specularite) in Matrix (Specularite (Fe2O3)) — mineral

Specular Hematite (Specularite) in Matrix

Specularite (Fe2O3)