Rock Identifier

Category

Sedimentary Or Igneous (Secondary Formation)

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

Ferruginous Quartz (Iron-stained Quartz (Silicon Dioxide, SiO2 with Fe2O3 inclusions)) — mineral

Ferruginous Quartz

Iron-stained Quartz (Silicon Dioxide, SiO2 with Fe2O3 inclusions)

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

Basalt-Amugydule (Amygdaloidal Basalt)

Aphanitic Mafic Igneous Rock with Vesicle Infillings

Quartz (Milky/Common) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Orange Calcite (Calcite (CaCO3)) — Mineral

Orange Calcite

Calcite (CaCO3)

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)

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

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

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

Carnelian (Red Chalcedony)

Silicon Dioxide (SiO2)

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)

Prehnite (Prehnite (Ca2Al2Si3O10(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al2Si3O10(OH)2)

Quartz Crystal (Quartz (SiO₂)) — Mineral

Quartz Crystal

Quartz (SiO₂)

Red Jasper (Red Jasper (variety of Chalcedony, SiO₂)) — Mineral

Red Jasper

Red Jasper (variety of Chalcedony, SiO₂)

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

Orange Calcite

Calcite (Calcium Carbonate, CaCO3)

Pyrite (Pyrite (Iron Disulfide), FeS2) — Mineral

Pyrite

Pyrite (Iron Disulfide), FeS2

Nuummite (Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)) — metamorphic

Nuummite

Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)

Agate (Silicon Dioxide (SiO2)) — mineral

Agate

Silicon Dioxide (SiO2)

Black Tourmaline (Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)) — Mineral

Black Tourmaline

Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)

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

Banded Gneiss (Gneiss (High-grade Regional Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Sandstone (Red) (Arenite (primarily Quartz, SiO2, with Iron Oxide cement)) — sedimentary

Sandstone (Red)

Arenite (primarily Quartz, SiO2, with Iron Oxide cement)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Basalt (Basalt) — Igneous

Basalt

Basalt

Turquoise (Turquoise (CuAl6(PO4)4(OH)8·4H2O)) — mineral

Turquoise

Turquoise (CuAl6(PO4)4(OH)8·4H2O)

Stichtite in Serpentine (Atlantasite) (Mg6Cr2CO3(OH)16·4H2O (Stichtite) within Mg3Si2O5(OH)4 (Serpentine)) — Metamorphic rock / Mineral variety

Stichtite in Serpentine (Atlantasite)

Mg6Cr2CO3(OH)16·4H2O (Stichtite) within Mg3Si2O5(OH)4 (Serpentine)

Metamorphic rock / Mineral variety

Quartz Geode (Nodule) (Silicon Dioxide (SiO2)) — sedimentary or igneous

Quartz Geode (Nodule)

Silicon Dioxide (SiO2)

sedimentary or igneous

Quartz (Quartz (SiO₂)) — Mineral

Quartz

Quartz (SiO₂)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Quartz (likely Jasper or Chert variety) (Quartz (SiO₂)) — Mineral

Quartz (likely Jasper or Chert variety)

Quartz (SiO₂)

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)

Dark Igneous Rock (Likely Basalt or Diabase) (Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.) — Igneous

Dark Igneous Rock (Likely Basalt or Diabase)

Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.

Banded Agate (specifically Carnelian Agate) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Agate (specifically Carnelian Agate)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chalcedony (specifically Agate or Carnelian variety) (Cryptocrystalline Silica (SiO2)) — mineral

Chalcedony (specifically Agate or Carnelian variety)

Cryptocrystalline Silica (SiO2)

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

Hematite

Iron(III) oxide (Fe2O3)

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

Hematite

Iron(III) oxide (Fe2O3)

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

Hematite

Iron(III) oxide (Fe2O3)