Granite Sand (Decomposed Granite)
Grus / Quartz-Feldspar Detritus
Category
Browse sedimentary rock (possibly a conglomerate or coarse grained sandstone) specimens identified by the Rock Identifier community.
Granite Sand (Decomposed Granite)
Grus / Quartz-Feldspar Detritus
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Shiva Lingam
Cryptocrystalline Quartz (Jasproid/Sandstone) with Iron Oxide (Fe2O3)
Banded Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Biotite/Amphiboles)
Dendrite (Manganese Oxide Dendrites)
Psilomelane or Pyrolusite on Matrix (typically MnO2)
Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone)
Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)
Schist
Schist (various mineral compositions)
Jasper (Iron-stained Quartzite/Chert)
Silicon Dioxide (SiO2) with iron oxide inclusions
Quartzite (River Cobble)
Quartzite (primarily SiO2)
Marble
Recrystallized Carbonate Rock (CaCO3)
Ironstone with Pyrite
Ferruginous Sandstone (Fe2O3) with minor Sulfide minerals (FeS2)
Shale (with minor calcite veining)
Clastic sedimentary rock (primarily clay minerals and quartz)
Gneiss
Gneiss (pronounced 'nice')
Wishing Stone (Basalt/Greywacke with Quartz Vein)
Basalt or Siltstone with SiO2 (Quartz) hydrothermal intrusion
Mica Schist with Garnet
Garnetiferous Mica Schist
Fossil Shell in Sedimentary Matrix
Bivalvia (fossil) in Calcium Carbonate Matrix
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Mica Schist
Mica Schist (primarily Muscovite and Biotite composition)
Pink Quartzite
Quartzite (primarily SiO2 with trace impurities of iron oxides)
Fossiliferous Limestone (Coquina / Shell Limestone)
Bioclastic Limestone (CaCO3)
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
Shale with Pyrite
Clastic sedimentary rock containing Iron Disulfide (FeS2)
Fossiliferous Brachiopod in Shale
Brachiopoda (Phylum) preserved in Carbonaceous Shale
Quartz
Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Turquoise
Hydrated phosphate of copper and aluminium - CuAl6(PO4)4(OH)8·4H2O
Biotite Schist
Biotite Schist
Banded Gneiss
Gneiss (pronounced 'nice')
Glacial Erratic (Sandstone/Quartzite)
Glacial Erratic specimen (likely Orthoquartzite or Feldspathic Sandstone)
River Pebbles (Stream-rounded rocks)
Fluvial Detritus (varied mineralogy)
Quartz (various varieties)
SiO₂ (Silicon Dioxide)
Bauxite
Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)
Gneiss (Stream-worn Cobble)
Gneiss (Metamorphic rock composed primarily of Quartz, Feldspar, and Mica)
Sandstone Pebble with Iron Staining
Clastic Sedimentary Rock (primarily Quartz with Fe2O3 oxides)
Quartz
Silicon Dioxide (SiO₂)
Ironstone Concretion (Limonite/Goethite)
Ferruginous Sandstone or Limonite (FeO(OH)·nH2O)
Bauxite
Bauxite (mixture of Hydrous Aluminum Oxides)
Ferruginous Sandstone (with possible trace fossils)
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)
Gneiss (specifically a Granitic Gneiss)
Gneiss (typically composed of Quartz, Feldspar, and Mica/Amphiboles)
River Stone (Granitic Gneiss)
Foliated Granitic Gneiss
Greenstone / Diabase Porphyry
Porphyritic Diabase (Micro-gabbro)
Schist with Biotite Inclusion
Biotite-bearing Mica Schist (K(Mg,Fe)3AlSi3O10(F,OH)2)