Pyrite
Iron Sulfide (FeS2)
Category
Browse sedimentary (chemically precipitated) or metamorphic specimens identified by the Rock Identifier community.
Pyrite
Iron Sulfide (FeS2)
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
Rough Emerald (Beryl)
Emerald (Be3Al2(SiO3)6 with Cr/V impurities)
Clear Quartz
Silicon Dioxide (SiO2)
Clear Quartz Crystal
Silicon Dioxide (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
Clear Quartz Crystal Cluster
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Banded Calcite (often sold as 'Travertine' or 'Mexican Onyx')
Calcium Carbonate (CaCO3)
Banded Calcite (often sold as 'Mexican Onyx' or 'Calcite Onyx')
Calcite (Calcium Carbonate, CaCO3)
Agate
Agate (Cryptocrystalline Variety of Quartz, SiO2)
Cobaltoan Calcite / Pink Dolomite (Possible)
Cobaltoan Calcite: (Ca,Co)CO3; Pink Dolomite (or Thulite): CaMg(CO3)2 or Mn-Dolomite / (Thulite: Mn2+3Al2(Si2O7)(SiO4)O(OH))
Arkosic Sandstone (or Conglomeritic Sandstone fragment)
Arkose (rich in feldspar)
Brecciated Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Coarse Sand Grain / Lithic Fragment
Clastic Sediment (Lithic fragment or Quartz/Feldspar grain)
Limestone (Cliff Formation)
Limestone (predominantly CaCO3 as calcite)
Gneiss
Gneiss
Gneiss (with Quartz-Feldspar vein)
Gneiss (high-grade metamorphic rock) containing Quartz (SiO2) and Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8)
Porphyritic Basalt (Chinese Writing Stone)
Porphyritic Basalt with Feldspar Phenocrysts
Chrysocolla
Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Limonite (after Pyrite Pseudomorph)
Limonite (Hydrated Iron Oxide Mixture, FeO(OH)·nH2O)
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained River Cobble)
Microcrystalline Quartz (SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Petrified Wood
Silicified Wood (SiO2)
Quartz (in a rock matrix)
Quartz (SiO2)
Banded Gneiss
Gneiss (Metamorphic high-grade rock)
Banded Gneiss
Gneiss (Metamorphic high-grade rock)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Green Aventurine
Silicon Dioxide with Fuchsite (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
Quartz Pebble (Milky and Gray)
Quartz (Silicon Dioxide, SiO2)
Garnet (Almandine variety)
Almandine, Fe3Al2(SiO4)3
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Magnetite
Magnetite (Fe3O4)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)