Garnet (Almandine)
Almandine, Fe3Al2(SiO4)3
Category
Browse sedimentary rock specimens identified by the Rock Identifier community.
Garnet (Almandine)
Almandine, Fe3Al2(SiO4)3
Chert (or Flint)
Silicon dioxide (SiO2)
Granite Sand (Decomposed Granite)
Grus / Quartz-Feldspar Detritus
Granite Gneiss
Felsic Gneiss
Gneiss
Gneiss (High-grade metamorphic rock)
Clear Quartz
Silicon Dioxide (SiO2)
Ferruginous Sandstone
Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)
Chert (Field Stone)
Microcrystalline / Cryptocrystalline Quartz (SiO2)
Coquina
Biogenic Limestone (CaCO3)
Bauxite
Bauxite (Mixture including Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Diaspore α-AlO(OH))
Bauxite
Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Travertine (Calcareous Tufa)
Calcium Carbonate (CaCO3)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Granite Cobble
Phaneritic Felsic Igneous Rock (Granite)
Sandstone
Arenite (composed primarily of SiO2)
Red Jasper
Jasper (SiO2) with Hematite (Fe2O3) inclusions
Tree Agate
Dendritic Chalcedony (SiO2)
Chert (Flint nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Red/Brown Variety)
Microcrystalline quartz (SiO2)
Chert (and/or Siltstone River Pebble)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Bauxite
Bauxite (mixture of Hydrous Aluminum Oxides)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Turquoise
CuAl6(PO4)4(OH)8·4H2O
Quartz Druzy Geode Fragment
Silicon Dioxide (SiO2)
Sandstone (Quartzose Sandstone)
Arenite (composed primarily of SiO2)
Sandstone
Arenite
Orthoceras Fossil in Limestone
Orthoceras (extinct genus of cephalopods), mineralized as Calcite (CaCO3) in Fossiliferous Limestone
Chert (Nodule)
Silicon Dioxide (SiO2)
Dyed Agate Slice
Silicon Dioxide (SiO2) with artificial colorants
Chert (specifically Jasper/Brown Chert)
Silicon Dioxide (SiO2)
Picture Jasper
Silicon dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Agate (Carnelian / Chalcedony)
Silicon Dioxide (SiO2)
Common Opal with Host Rock
Opal (Hydrated silica, SiO2·nH2O)
Sandstone (specifically Red Sandstone)
Arenite (SiO2 with Iron Oxide)
Sandstone (Red)
Arenite (primarily SiO2 with Iron Oxide staining)
Blue Kyanite
Kyanite (Al2SiO5)
Jasper
Silicon Dioxide (SiO2)
Halite (Rock Salt)
Halite (NaCl)
Halite (Rock Salt)
Halite (Sodium Chloride, NaCl)
Red Sandstone
Arenite (Fe2O3 rich)