Rock Identifier

Category

Sedimentary Or Igneous (Secondary Formation)

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

Learn about Sedimentary Or Igneous (Secondary Formation) in the encyclopedia

Banded Iron Formation

Banded Iron Formation

Itabirite

Jaspillite

Carbonatite

Conglomerate

Quartzite Sandstone

Quartzite Sandstone

Breccia

Ironstone

Lamproite

Troctolite

Basalt

Gabbro

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

River Rock (Gneiss/Schist mix) (Foliated Metamorphic Rock (Gneiss)) — metamorphic

River Rock (Gneiss/Schist mix)

Foliated Metamorphic Rock (Gneiss)

Likely hematite-rich iron ore (Hematite (Fe₂O₃), possibly with magnetite and/or goethite) — mineral

Likely hematite-rich iron ore

Hematite (Fe₂O₃), possibly with magnetite and/or goethite

Specular Hematite with Quartz (Ferric oxide (Fe2O3) and Silicon dioxide (SiO2)) — Mineral

Specular Hematite with Quartz

Ferric oxide (Fe2O3) and Silicon dioxide (SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Unknown Rock Fragment (Undetermined) — igneous

Unknown Rock Fragment

Undetermined

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Magnetite (Loadstone candidate) (Iron(II,III) oxide (Fe3O4)) — mineral

Magnetite (Loadstone candidate)

Iron(II,III) oxide (Fe3O4)

Rounded brown pebble, likely weathered basalt or iron-rich chert (Indeterminate; possibly basalt (fine-grained mafic silicate rock) or ferruginous chert) — igneous

Rounded brown pebble, likely weathered basalt or iron-rich chert

Indeterminate; possibly basalt (fine-grained mafic silicate rock) or ferruginous chert

Pyrite (Iron Disulfide (FeS2)) — Mineral

Pyrite

Iron Disulfide (FeS2)

Hematite (Iron Oxide (Fe2O3)) — mineral

Hematite

Iron Oxide (Fe2O3)

Quartzite Pebble (with iron staining) (Quartzite (SiO2 with ferric oxide impurities)) — metamorphic

Quartzite Pebble (with iron staining)

Quartzite (SiO2 with ferric oxide impurities)

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

Celestite (Celestine)

Strontium Sulfate (SrSO4)

Prehnite (Prehnite (Ca2Al(AlSi3O10)(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Fossiliferous limestone (likely crinoidal or shell limestone) (Calcite-rich limestone; predominantly CaCO₃, with visible fossil fragments) — fossil

Fossiliferous limestone (likely crinoidal or shell limestone)

Calcite-rich limestone; predominantly CaCO₃, with visible fossil fragments

Garnet-Bearing Gneiss (Garnetiferous Feldspathic Gneiss) — metamorphic

Garnet-Bearing Gneiss

Garnetiferous Feldspathic Gneiss

Polished jasper pebble (possibly orbicular jasper) (Microcrystalline quartz (SiO₂), likely jasper; exact variety cannot be confirmed visually) — igneous

Polished jasper pebble (possibly orbicular jasper)

Microcrystalline quartz (SiO₂), likely jasper; exact variety cannot be confirmed visually

Arkosic Sandstone (or Conglomeritic Sandstone fragment) (Arkose (rich in feldspar)) — sedimentary

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)

Prehnite (Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate hydroxide)) — mineral

Prehnite

Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate hydroxide)

Turquoise (Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)) — mineral

Turquoise

Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)

Sandstone or Mudstone with Iron Staining (Ferruginous Sandstone/Mudstone) — Sedimentary

Sandstone or Mudstone with Iron Staining

Ferruginous Sandstone/Mudstone

Small translucent quartz fragment (Quartz (SiO₂), possibly milky or near-colorless quartz) — mineral

Small translucent quartz fragment

Quartz (SiO₂), possibly milky or near-colorless quartz

Banded Agate (Chalcedony (SiO2) with impurities) — mineral

Banded Agate

Chalcedony (SiO2) with impurities

Unidentified Rock Fragment (Unknown) — Rock

Unidentified Rock Fragment

Unknown

Heulandite with Stilbite (Heulandite-Ca ((Ca,Na)2-3Al3(Al,Si)2Si13O36·12H2O) and Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O)) — mineral

Heulandite with Stilbite

Heulandite-Ca ((Ca,Na)2-3Al3(Al,Si)2Si13O36·12H2O) and Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O)

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

Calcite

Calcite (Calcium Carbonate, CaCO3)

Weathered polymictic rock fragment, likely granite-rich conglomerate (Indeterminate mixed lithology; apparent granitic clasts containing quartz, feldspar, and dark mafic minerals) — igneous

Weathered polymictic rock fragment, likely granite-rich conglomerate

Indeterminate mixed lithology; apparent granitic clasts containing quartz, feldspar, and dark mafic minerals

Banded River Cobble with Mafic Dike (Hydrothermally altered Graywacke or Sandstone with Mafic Intrusion) — igneous and sedimentary

Banded River Cobble with Mafic Dike

Hydrothermally altered Graywacke or Sandstone with Mafic Intrusion

igneous and sedimentary

Agate Geode (Cryptocrystalline Quartz (SiO2)) — mineral

Agate Geode

Cryptocrystalline Quartz (SiO2)

Folded Schist / Gneiss (Metamorphic Rock) (Regional Metaphoric Folded Outcrop (predominantly Schist/Gneiss)) — metamorphic

Folded Schist / Gneiss (Metamorphic Rock)

Regional Metaphoric Folded Outcrop (predominantly Schist/Gneiss)

Likely rough quartz-bearing mineral specimen (Quartz (silicon dioxide, SiO₂), possibly iron-stained quartz or quartz-rich rock) — mineral

Likely rough quartz-bearing mineral specimen

Quartz (silicon dioxide, SiO₂), possibly iron-stained quartz or quartz-rich rock

Red Jasper (Silicon dioxide (SiO2)) — mineral

Red Jasper

Silicon dioxide (SiO2)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Carnelian (Red Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Carnelian (Red Chalcedony)

Silicon Dioxide (SiO2)

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

Specular Hematite

Iron(III) oxide (Fe2O3)

River Pebble (Granite/Sandstone Pebble) (Rounded Quartz/Feldspar Gravel Clast) — igneous

River Pebble (Granite/Sandstone Pebble)

Rounded Quartz/Feldspar Gravel Clast

Hematite (Iron oxide (Fe2O3)) — mineral

Hematite

Iron oxide (Fe2O3)

Magnetite / Iron Ore (Magnetite (Fe3O4)) — mineral

Magnetite / Iron Ore

Magnetite (Fe3O4)

Magnetite (Iron Ore) (Magnetite (Fe3O4)) — mineral

Magnetite (Iron Ore)

Magnetite (Fe3O4)

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

Hematite

Iron(III) oxide (Fe2O3)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

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

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)