Rock Identifier

Category

Mineral Precipitate (Anthropogenic Context)

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

Cullet (Slag Glass) (Amorphous Silica (SiO2) with various metal oxide colorants) — mineraloid / anthropogenic

Cullet (Slag Glass)

Amorphous Silica (SiO2) with various metal oxide colorants

mineraloid / anthropogenic

Onyx Marble (Banded Calcite) (Calcite (Calcium Carbonate, CaCO3)) — sedimentary

Onyx Marble (Banded Calcite)

Calcite (Calcium Carbonate, CaCO3)

Amethyst (Amethyst (Silicon Dioxide, SiO2)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Satin Spar (often marketed as Selenite) (Fibrous Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O) — mineral

Satin Spar (often marketed as Selenite)

Fibrous Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Milky or Iron-Stained Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky or Iron-Stained Quartz

Quartz (Silicon Dioxide, SiO2)

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

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Agate (specifically Lace Agate or Banded Agate) (Silicon Dioxide (SiO2)) — mineral

Agate (specifically Lace Agate or Banded Agate)

Silicon Dioxide (SiO2)

Desert Rose (Gypsum (variety Selenite) - CaSO4·2H2O) — mineral

Desert Rose

Gypsum (variety Selenite) - CaSO4·2H2O

Red Agate (Agate (Cryptocrystalline variety of Quartz, SiO2)) — mineral

Red Agate

Agate (Cryptocrystalline variety of Quartz, SiO2)

Carnelian (Carnelian (Cryptocrystalline Quartz, SiO2)) — mineral

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

Orbicular Jasper (Ocean Jasper) (Silicon Dioxide (SiO2) with iron and magnesium inclusions) — mineral

Orbicular Jasper (Ocean Jasper)

Silicon Dioxide (SiO2) with iron and magnesium inclusions

Banded Agate (Dyed Purple) (Agate (Variety of Chalcedony/Quartz), SiO2) — mineral

Banded Agate (Dyed Purple)

Agate (Variety of Chalcedony/Quartz), SiO2

Rutilated Quartz (Quartz (SiO2) with Rutile (TiO2) inclusions) — Mineral

Rutilated Quartz

Quartz (SiO2) with Rutile (TiO2) inclusions

Chert / Flint (Cryptocrystalline quartz (SiO2)) — Sedimentary

Chert / Flint

Cryptocrystalline quartz (SiO2)

Rough Quartz Crystal in Matrix (Silicon Dioxide (SiO2)) — mineral

Rough Quartz Crystal in Matrix

Silicon Dioxide (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

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

Carnelian

Carnelian (variety of Chalcedony, SiO2)

Blue Lace Agate (Banded Chalcedony) (Silicon Dioxide (SiO₂)) — mineral

Blue Lace Agate (Banded Chalcedony)

Silicon Dioxide (SiO₂)

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

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

Ferruginous Slag (Iron Smelting Byproduct) (Anthropogenic Vitreous Silicate (often containing Fayalite: Fe2SiO4)) — Mineraloid/Anthropogenic (Technofossil)

Ferruginous Slag (Iron Smelting Byproduct)

Anthropogenic Vitreous Silicate (often containing Fayalite: Fe2SiO4)

Mineraloid/Anthropogenic (Technofossil)

Pyrite in Quartz (Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)) — mineral

Pyrite in Quartz

Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)

Vesicular Basalt (Amygdaloidal Basalt (Mafic extrusive volcanic rock)) — Igneous

Vesicular Basalt

Amygdaloidal Basalt (Mafic extrusive volcanic rock)

Agate (specifically Waterline or Onyx-type Agate) (Silicon Dioxide (SiO2) - variety Chalcedony) — mineral

Agate (specifically Waterline or Onyx-type Agate)

Silicon Dioxide (SiO2) - variety Chalcedony

Pumice or Tufa/Travertine (Pumice (if igneous) or Calcareous Tufa (if sedimentary)) — igneous/sedimentary

Pumice or Tufa/Travertine

Pumice (if igneous) or Calcareous Tufa (if sedimentary)

igneous/sedimentary

Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

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

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

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

Magnetite / Iron Ore

Magnetite (Fe3O4)

Greywacke with Quartz Veins (Lithic Sandstone (Greywacke) with SiO2 inclusions) — sedimentary

Greywacke with Quartz Veins

Lithic Sandstone (Greywacke) with SiO2 inclusions

Dendritic Limestone (Calcite with Manganese Oxide (Manganese Dendrites)) — sedimentary

Dendritic Limestone

Calcite with Manganese Oxide (Manganese Dendrites)

Veined Limestone (Micrite) with Quartz/Calcite Veins (Calcium Carbonate (CaCO3) with Silicate or Carbonate inclusions) — sedimentary

Veined Limestone (Micrite) with Quartz/Calcite Veins

Calcium Carbonate (CaCO3) with Silicate or Carbonate inclusions

Agate and Amethyst (Quartz variants) (Silicon Dioxide (SiO2) - Microcrystalline Quartz and Crystalline Quartz) — mineral

Agate and Amethyst (Quartz variants)

Silicon Dioxide (SiO2) - Microcrystalline Quartz and Crystalline Quartz

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

Celestite Geode

Celestine (Strontium Sulfate, SrSO4)

Shale creek bed (Shale (fine-grained clastic sedimentary rock)) — Sedimentary

Shale creek bed

Shale (fine-grained clastic sedimentary rock)

Quartz Vein in River Siltstone (Crystalline Quartz (SiO2) in Siliclastic Matrix) — sedimentary

Quartz Vein in River Siltstone

Crystalline Quartz (SiO2) in Siliclastic Matrix

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

Carnelian

Silicon Dioxide (SiO2) - variety of Chalcedony

Desert Rose (Gypsum Variety) (Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O) — mineral

Desert Rose (Gypsum Variety)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Gold in Quartz (Hydrothermal Quartz with Native Gold (SiO2 with Au)) — mineral

Gold in Quartz

Hydrothermal Quartz with Native Gold (SiO2 with Au)

Blue Agate (Dyed) (Silicon Dioxide (SiO2) - Variety of Chalcedony) — mineral

Blue Agate (Dyed)

Silicon Dioxide (SiO2) - Variety of Chalcedony

Dendrite (Manganese Oxide Dendrites) (Psilomelane or Pyrolusite on Matrix (typically MnO2)) — mineral

Dendrite (Manganese Oxide Dendrites)

Psilomelane or Pyrolusite on Matrix (typically MnO2)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Sandstone (Picture Sandstone) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Picture Sandstone)

Arenite (primarily SiO2)