Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (primarily SiO2)
Category
Browse industrial byproduct (often mistaken for obsidian or mineral) specimens identified by the Rock Identifier community.
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (primarily SiO2)
Milky Quartz (Water-Worn Pebble)
Quartz (Silicon Dioxide, SiO2)
Blue Calcite
Calcium Carbonate (CaCO3)
Nickel
Nickel (Ni)
Schist
Mica Schist
Sandstone
Sandstone (clastic sedimentary rock), primarily SiO2
Quartz Vein in Granite
Crystalline Silicon Dioxide (SiO2) in Granitic Matrix
Banded Agate
Agate (Silicon Dioxide, SiO2)
Chert / Flint Nodules in Limestone
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
Schist
Crystalline Schist (often containing Muscovite, Biotte, or Quartz)
Iron-stained Quartz (Gossan/Limonite-coated Quartz)
Silicon Dioxide (SiO2) with Hydrated Iron Oxides (FeO(OH)·nH2O)
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
Rough Diamond
Diamond (Native Carbon, C)
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Pegmatite with Black Tourmaline
Granitic Pegmatite with Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)
Yellow Quartz (Citrine/Quartzite Pebble)
Silicon Dioxide (SiO2)
Yellow Quartz Pebble
SiO2 (Silicon Dioxide)
Bauxite
Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)
Gold and Diamond
Native Gold (Au) and Diamond (C)
Sandstone
Arenite (primarily SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Green Fluorite
Fluorite (Calcium Fluoride - CaF2)
Corundum (Sapphire and Ruby)
Aluminum Oxide (Al2O3)
Magnetic Hematite (Man-made)
Iron Oxide (Fe2O3) with Barium-Strontium Ferrite
Greenschist
Greenschist (chlorite-epidote schist)
Yellow Chalcedony
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz (Peach/Orange variety)
Silicon Dioxide (SiO2)
Quartz (Sunstone-like Chalcedony)
Silicon Dioxide (SiO2)
White Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Shale (possibly Carbonaceous or Oil Shale)
Argillaceous Sedimentary Rock
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
River Quartz Pitting/Cobble
Silicon Dioxide (SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Rough Diamond
Diamond (pure Carbon, C)
Red Sandstone
Arenite (primarily Quartz with Hematite cement)
Bull Quartz (Milky Quartz)
Quartz (Silicon Dioxide - SiO2)