Garnet (Almandine)
Almandine, Fe3Al2Si3O12
Category
Browse sedimentary or mineral specimens identified by the Rock Identifier community.
Garnet (Almandine)
Almandine, Fe3Al2Si3O12
Specular Hematite with Quartz and Limonite
Hematite (Fe2O3) with Quartz (SiO2) and Limonite (FeO(OH)·nH2O)
Dyed Howlite (Dyed Red)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Optical Calcite (Iceland Spar)
Calcite (CaCO3)
Quartz (Milky or Yellow variety)
Silicon Dioxide (SiO2)
Native Gold (in earring form)
Gold (Au)
Calcite
Calcium Carbonate (CaCO3)
Pyrite with Iron Oxides (Fool's Gold in Matrix)
Iron Sulfide (FeS2)
Orange Calcite
Calcium Carbonate (CaCO3)
Chalcedony
Silicon Dioxide (SiO2)
Agate
Banded Chalcedony (SiO2)
Specular Hematite (Polished Sphere)
Hematite (Alpha Fe2O3)
Blue Chalcedony (likely dyed Agate)
Silicon Dioxide (SiO₂)
Orange Calcite
Calcium Carbonate (CaCO3)
Sandstone
Arenite
Red Sandstone
Arenite (Ferruginous Sandstone)
Yellow Chalcedony or River Jasper
Silicon Dioxide (SiO2)
Quartz Pebble
Crystalline Silica (SiO2)
Quartz (Milky / Massive Quartz)
Silicon Dioxide (SiO2)
Specularite in Quartz
Specular Hematite (Fe2O3) in Quartz (SiO2)
Celestine (or Celestite) on Matrix
Celestine (SrSO4)
Milky Quartz
Silicon Dioxide (SiO2)
Chalcedony
Chalcedony (SiO2)
Quartzite and Sandstone Pebbles
Silicon dioxide (SiO2)
Concretion
Septarian or Siderite Concretion
Granite Gneiss
Gneiss (High-grade Metamorphic Rock)
Crinoidean Fossil (Stem Fragment)
Phylum Echinodermata, Class Crinoidea
Yellow Jasper
Silicon Dioxide (SiO2) with goethite or iron oxide inclusions
Sandstone
Arenite (primarily SiO2)
Hematite
Iron Oxide (Fe2O3)
Hematite
Iron Oxide (Fe2O3)
Quartz Geode (Unbroken)
Silicon Dioxide (SiO2)
Hematite
Iron Oxide (Fe2O3)
Pyrite
Iron Disulfide (FeS2)
Carnelian (Red Agate)
Carnelian (SiO2 with Hematite inclusions)
Pyrite
Iron Sulfide (FeS2)
Quartz Geode (Druzy Quartz)
Silicon Dioxide (SiO2)
Banded Agate (Onyx type)
Silicon Dioxide (SiO2)
Pyrite in Matrix
Iron Sulfide (FeS2)
Banded Agate
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Quartz Geode
Silicon Dioxide (SiO2)
Satin Spar (often sold as Selenite)
Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)