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

Hematite (Iron Oxide (Fe2O3)) — mineral

Hematite

Iron Oxide (Fe2O3)

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

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Basalt (Basalt) — Igneous

Basalt

Basalt

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

Yellow Calcite

Calcite (Calcium Carbonate, CaCO3)

Pink Tourmaline in Quartz (Elbaite [Na(Li,Al)3Al6(BO3)3Si6O18(OH)4] in Quartz [SiO2]) — igneous

Pink Tourmaline in Quartz

Elbaite [Na(Li,Al)3Al6(BO3)3Si6O18(OH)4] in Quartz [SiO2]

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

Limonite / Goethite Ironstone Concretion (FeO(OH)·nH2O (Hydrated Iron Oxide)) — mineral

Limonite / Goethite Ironstone Concretion

FeO(OH)·nH2O (Hydrated Iron Oxide)

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

Quartz on Matrix

Silicon Dioxide (SiO2)

Pyrite (Iron Disulfide (FeS2)) — Mineral

Pyrite

Iron Disulfide (FeS2)

Hematite (Iron oxide (Fe2O3)) — mineral

Hematite

Iron oxide (Fe2O3)

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

River Pebble (Granite/Sandstone Pebble)

Rounded Quartz/Feldspar Gravel Clast

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

Carnelian (Red Chalcedony)

Silicon Dioxide (SiO2)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

Specular Hematite

Iron(III) 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)

Red Jasper (Silicon dioxide (SiO2)) — mineral

Red Jasper

Silicon dioxide (SiO2)

Red Hematite (Banded Iron Formation) (Hematite (Fe2O3)) — mineral

Red Hematite (Banded Iron Formation)

Hematite (Fe2O3)

Jasper (Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)) — sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)

Black Tourmaline (Schorl) (Schorl (Na(Fe^2+)3Al6(Si6O18)(BO3)3(OH)4)) — Mineral

Black Tourmaline (Schorl)

Schorl (Na(Fe^2+)3Al6(Si6O18)(BO3)3(OH)4)

Granite (Granite (composed mainly of Quartz, Feldspar, and Mica)) — igneous

Granite

Granite (composed mainly of Quartz, Feldspar, and Mica)

Quartz (Tumbled) (Silicon Dioxide (SiO2)) — mineral

Quartz (Tumbled)

Silicon Dioxide (SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Magnetite (Magnetite (Fe3O4)) — Mineral

Magnetite

Magnetite (Fe3O4)

Quartz (likely milky/rose quartz variety) (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz (likely milky/rose quartz variety)

Quartz (SiO2 - Silicon Dioxide)

Granite (Granite) — igneous

Granite

Granite

Basalt-Amugydule (Amygdaloidal Basalt) (Aphanitic Mafic Igneous Rock with Vesicle Infillings) — igneous

Basalt-Amugydule (Amygdaloidal Basalt)

Aphanitic Mafic Igneous Rock with Vesicle Infillings

Turquoise color-bead and Hematite necklace (Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Hematite (Fe2O3)) — mineral

Turquoise color-bead and Hematite necklace

Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Hematite (Fe2O3)

Green Quartz (including Prase or Aventurine variants) (Silicon Dioxide (SiO2) with inclusions (likely Actinolite or Chlorite)) — mineral

Green Quartz (including Prase or Aventurine variants)

Silicon Dioxide (SiO2) with inclusions (likely Actinolite or Chlorite)

Carnelian (Carnelian (a variety of Chalcedony, SiO

₂)) — Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)

Carnelian

Carnelian (a variety of Chalcedony, SiO ₂)

Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)

Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

Gneiss (Gneissic Metamorphic Rock) — metamorphic

Gneiss

Gneissic Metamorphic Rock

Druzy Quartz on Host Rock (Silicon Dioxide (SiO2) with various iron-oxide inclusions) — mineral

Druzy Quartz on Host Rock

Silicon Dioxide (SiO2) with various iron-oxide inclusions

Hematite (Iron Oxide (Fe2O3)) — mineral

Hematite

Iron Oxide (Fe2O3)

Hematite (Iron Oxide (Fe2O3)) — mineral

Hematite

Iron Oxide (Fe2O3)

Hematite (Iron Oxide (Fe2O3)) — mineral

Hematite

Iron Oxide (Fe2O3)

Magnetite (Lodestone variant potential) (Magnetite (Fe3O4)) — mineral

Magnetite (Lodestone variant potential)

Magnetite (Fe3O4)

White Quartz (Silicon Dioxide (SiO2)) — mineral

White Quartz

Silicon Dioxide (SiO2)

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

Hematite

Iron(III) oxide (Fe2O3)

Banded Agate (specifically Carnelian Agate slice) (Chalcedony (cryptocrystalline variety of Quartz), SiO2) — mineral

Banded Agate (specifically Carnelian Agate slice)

Chalcedony (cryptocrystalline variety of Quartz), SiO2

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

Magnetite / Iron Ore

Magnetite (Fe3O4)