Garnet-Bearing Gneiss
Almandine-Garnet Gneiss
metamorphic
Category
Sedimentary (Base), Then Artificial
Browse sedimentary (base), then artificial specimens identified by the Rock Identifier community.
Schist (specifically Mica Schist)
Mica Schist (primarily composed of Muscovite KAl2(AlSi3O10)(OH)2 and Biotite)
metamorphic
Muscovite Mica
Muscovite - KAl2(AlSi3O10)(OH)2
mineral
Limonite (Iron Stone)
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
mineral
Biotite (Black Mica)
Biotite (K(Mg,Fe)3AlSi3O10(OH)2)
mineral
Mica Schist with Iron Staining
Muscovite/Biotite Schist
metamorphic
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
metamorphic
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix
Metamorphic or Igneous (context dependent)
Dendritic Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions
mineral
Chert breccia
Sedimentary Breccia (Microcrystalline Quartz)
sedimentary
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Glauconitic Sandstone
Glauconitic arenite (contains (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Anthracite Coal
Anthracite (Carbon-based organic sedimentary rock transitioned to metamorphic)
metamorphic
Greenstone
Metamorphosed Mafic Igneous Rock
metamorphic
River Rocks and Pebbles
Mixed Silica-rich Sediments (SiO2 based)
sedimentary
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)
mineral
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Favosites Fossil (Honeycomb Coral)
Favosites sp. (Extinct genus of tabulate coral)
sedimentary
Glauconitic Sandstone (Greensand)
Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2
sedimentary
Gold Nugget
Native Gold (Au)
mineral
Chert (Field-collected Arrowhead-shaped Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Coquina
Biogenic Limestone (Calcite, CaCO3)
sedimentary
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 inclusions)
sedimentary
Rough Emerald (Beryl)
Emerald (Be3Al2(SiO3)6 with Cr/V impurities)
mineral
Ferruginous Sandstone
Arenite with Iron Oxide cement (Fe2O3 / FeO(OH))
sedimentary
Coquina
Coquina (Biogenic Limestone / CaCO3)
sedimentary
Ferruginous Sandstone (Iron-rich Sandstone)
Ferruginous Arenite
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Mica Schist
Foliated Metamorphic Rock (Schist)
metamorphic
Iron-Stained Quartzite
Recrystallized Meta-Quartzite (primarily SiO2)
metamorphic
Green Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Bumblebee Jasper
Fossiliferous Calcite containing Orpiment and Realgar
sedimentary
Mica Schist
Mica Schist
metamorphic
Biotite (Black Mica)
Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2
mineral
Schist (Micaceous Schist)
Schist (comprising Muscovite/Biotite mica, Quartz, and Feldspar)
metamorphic
Limonite (Iron Ore/Sandstone mixture)
Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix
mineral
Water and Silt (Sedimentary Environment)
Suspended Sediment / H2O (dihydrogen monoxide)
sedimentary
Mica Schist (with Golden/Biotite inclusions)
K(Mg,Fe)3AlSi3O10(F,OH)2 (Biotite), KAl2(AlSi3O10)(F,OH)2 (Muscovite)
metamorphic
Dalmatian Jasper (Dalmatian Stone)
Dalmatian Stone (primarily Feldspar, Quartz, and Arfvedsonite/Tourmaline)
igneous
Chert (Yellow Jasper variant)
Silicon Dioxide (SiO2)
sedimentary
Graphite
Graphite (Native Carbon, C)
metamorphic