Quartz (Milky/Iron-stained)
Silicon Dioxide (SiO2)
Category
Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.
Quartz (Milky/Iron-stained)
Silicon Dioxide (SiO2)
Quartzite with Hematite staining
Quartzite (SiO2) with iron oxide inclusions
Carnelian Agate
Chalcedony (Silicon Dioxide, SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Rhodolite Garnet
Magnesium Aluminum Silicate; formula: (Mg,Fe)3Al2(SiO4)3
Psilomelane (Black Hematite/Manganese Ore)
Barium Manganese Oxide (Formula: BaMn9O18(OH)4)
Greenstone / Chert
Cryptocrystalline Quartz (SiO2) or Altered Basalt
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Clear Quartz Crystal
Silicon Dioxide (SiO2)
Botryoidal Agate
Chalcedony (Silicon Dioxide, SiO2)
Blue Calcite (commonly sold as Caribbean Calcite)
Calcium Carbonate (CaCO3)
Blue Calcite
Calcium Carbonate (CaCO3)
Pink Calcite (Mangano Calcite)
Calcium Carbonate (CaCO3)
Chert (Jasper/Agate variety)
Microcrystalline quartz (SiO2)
Blue Chalcedony
Chalcedony (Silicon Dioxide, SiO2)
Calcite
Calcite (Mineral, Calcium Carbonate - CaCO3)
Granite with Epidote
Granite, containing quartz, feldspar, and epidote
Red Jasper (Opaque Chalcedony)
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Rough Agate/Chert Nodules
Cryptocrystalline Quartz (SiO2)
Pyrite
Iron Pyrite (FeS₂)
Chert (with Quartz vein)
Chert (Silicon Dioxide, SiO2)
Pyrite
Pyrite (FeS₂)
Magnetite (Lodestone variety)
Magnetite (Fe3O4)
Quartz with Iron Staining
Silicon Dioxide (SiO2) with iron oxide impurities
Milky or Iron-Stained Quartz
Quartz (Silicon Dioxide, SiO2)
Magnetite Orthorthotropic Rock
Magnetite (Fe3O4)
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
White Agate (Chalcedony)
Silicon Dioxide (SiO2)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with iron impurities)
Blue Calcite
Calcium Carbonate (CaCO3)
Turquoise
Hydrated phosphate of copper and aluminum - CuAl6(PO4)4(OH)8·4H2O
Agate Geode
Chalcedony (SiO2 - Silicon Dioxide)
Gold Nugget
Native Gold (Au)
Limestone
Calcium Carbonate (CaCO3)
Quartzite Pebble (with iron staining)
Quartzite (SiO2 with ferric oxide impurities)
Red Quartz (Carnelian/Red Jasper Agate)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Magnetite / Hematite mix (Iron Ore)
Fe3O4 (Magnetite) / Fe2O3 (Hematite)
Magnetite (Lodestone)
Magnetite (Fe3O4)
Gneiss (specifically a weathered Amphibolite or Garnet Gneiss)
Gneiss (complex silicate composition)