Rock Identifier

Category

Mineral Precipitate (Anthropogenic Context)

Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.

Green Calcite (Calcium Carbonate (CaCO3)) — mineral

Green Calcite

Calcium Carbonate (CaCO3)

Milky Quartz Vein in Host Rock (Silicon Dioxide (SiO2)) — mineral

Milky Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

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

Chalcedony Nodule (Carnelian/Agate)

Chalcedony (Silicon Dioxide, SiO2)

Fluorite (likely Fluorite on Quartz/Matrix) (Calcium Fluoride (CaF2)) — mineral

Fluorite (likely Fluorite on Quartz/Matrix)

Calcium Fluoride (CaF2)

Amethyst on Agate/Basalt Matrix (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst on Agate/Basalt Matrix

Silicon Dioxide (SiO2) with iron impurities

Agate (Geode nodule) (Cryptocrystalline Quartz (SiO2)) — mineral

Agate (Geode nodule)

Cryptocrystalline Quartz (SiO2)

Quartz (Milky or Cloudy Quartz) (Quartz (Silicon Dioxide, SiO2)) — mineral

Quartz (Milky or Cloudy Quartz)

Quartz (Silicon Dioxide, SiO2)

Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx') (Calcite (Calcium Carbonate, CaCO3)) — sedimentary

Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')

Calcite (Calcium Carbonate, CaCO3)

Coquina (Biogenic Limestone (Coquina)) — sedimentary

Coquina

Biogenic Limestone (Coquina)

Banded Iron Formation (BIF) (Banded Iron Formation (predominantly Hematite Fe2O3 and magnetite Fe3O4 alternating with Chert SiO2)) — sedimentary

Banded Iron Formation (BIF)

Banded Iron Formation (predominantly Hematite Fe2O3 and magnetite Fe3O4 alternating with Chert SiO2)

Moqui Marble (Iron Oxide Concretion (Limonite/Hematite over Sandstone)) — sedimentary

Moqui Marble

Iron Oxide Concretion (Limonite/Hematite over Sandstone)

Chert (with Quartz vein/coating) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Quartz vein/coating)

Microcrystalline Quartz (SiO2)

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

Quartz Geode (Nodule)

Silicon Dioxide (SiO2)

sedimentary or igneous

Sandstone with Concretions / Liesegang Rings (Arenite with iron oxide banding) — sedimentary

Sandstone with Concretions / Liesegang Rings

Arenite with iron oxide banding

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

Calcite

Calcite (Calcium Carbonate, CaCO3)

Bog Iron / Limonite Concretion (Goethite/Limonite mixture (FeO(OH)·nH2O)) — sedimentary

Bog Iron / Limonite Concretion

Goethite/Limonite mixture (FeO(OH)·nH2O)

Amygdaloidal Basalt with Quartz/Calcite Inclusions (Amygdaloidal Basalt (SiO2 / CaCO3 inclusions)) — igneous

Amygdaloidal Basalt with Quartz/Calcite Inclusions

Amygdaloidal Basalt (SiO2 / CaCO3 inclusions)

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

Green Calcite

Calcite (Calcium Carbonate, CaCO3)

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Chalcedony (Botryoidal/Drusy Quartz) (Silicon Dioxide (SiO₂)) — Mineral

Chalcedony (Botryoidal/Drusy Quartz)

Silicon Dioxide (SiO₂)

Aragonite (Aragonite (Calcium Carbonate - CaCO3)) — mineral

Aragonite

Aragonite (Calcium Carbonate - CaCO3)

Dendritic Agate (Tumbled) (Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions) — mineral

Dendritic Agate (Tumbled)

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Green Agate (Silicon dioxide (SiO₂)) — mineral

Green Agate

Silicon dioxide (SiO₂)

Quartz (possibly milky quartz or quartz with inclusions) (SiO2 (Silicon Dioxide)) — Mineral

Quartz (possibly milky quartz or quartz with inclusions)

SiO2 (Silicon Dioxide)

Ferruginous Sandstone (Gritstone) (Arenite with Iron-Oxide Cement (SiO2 with Fe2O3 and FeO(OH))) — sedimentary

Ferruginous Sandstone (Gritstone)

Arenite with Iron-Oxide Cement (SiO2 with Fe2O3 and FeO(OH))

Quartz with Chlorite or Hornblende inclusions (Silicon dioxide (SiO2) with phyllosilicate or amphibole inclusions) — metamorphic

Quartz with Chlorite or Hornblende inclusions

Silicon dioxide (SiO2) with phyllosilicate or amphibole inclusions

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Quartz (Chert/Chalcedony variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Jasper (Red Jasper) (Jasper (SiO2 - Silicon Dioxide with iron inclusions)) — sedimentary

Jasper (Red Jasper)

Jasper (SiO2 - Silicon Dioxide with iron inclusions)

Sandstone with Ironstone Concretion (Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))) — sedimentary

Sandstone with Ironstone Concretion

Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))

Septarian Nodule (Dragon Stone) (Septarian concretion (CaCO3 with Aragonite and Calcite)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian concretion (CaCO3 with Aragonite and Calcite)

Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

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

Hematite

Iron(III) oxide (Fe2O3)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

White Quartz (Silicon Dioxide (SiO2)) — mineral

White Quartz

Silicon Dioxide (SiO2)

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Green Calcite (Calcium Carbonate (CaCO3)) — mineral

Green Calcite

Calcium Carbonate (CaCO3)

Rhodochrosite with Pyrite and Quartz (Manganese Carbonate (MnCO3)) — mineral

Rhodochrosite with Pyrite and Quartz

Manganese Carbonate (MnCO3)