Mahogany Obsidian
Obsidian (volcanic glass with Hematite/Magnetite inclusions)
Category
Browse sedimentary (chemical) specimens identified by the Rock Identifier community.
Mahogany Obsidian
Obsidian (volcanic glass with Hematite/Magnetite inclusions)
Quartzite Pebble (with Iron Staining)
Quartzite (SiO2)
Quartzite
Quartzite (primarily SiO2)
Mahogany Obsidian
Obsidian (Volcanic Glass) with Hematite or Magnetite inclusions, SiO2 (Silicon Dioxide)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (SiO2)
Shale
Fissile mudstone (Shale)
Quartzite Pebbles
Quartzite (SiO2)
Quartzite
Quartzite (SiO2)
Quartz (Riverstone / Cobble)
Silicon Dioxide (SiO2)
Azurite
Azurite (Cu3(CO3)2(OH)2)
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Gold Nugget
Native Gold (Au)
Black Obsidian
Volcanic Glass (predominantly SiO2)
Silty Shale
Silty Shale (Fissile Sedimentary Rock)
Shale
Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)
Shale (Ferruginous)
Laminated Mudrock (Siliciclastic Sedimentary Rock)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Shale (with Iron Oxide staining)
Fissile Mudstone (primarily Quartz and Clay minerals)
Brachiopod Fossil in Limestone
Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)
Sedimentary Breccia
Breccia (Clastic Sedimentary Rock)
Pyrite
Pyrite (Iron sulfide, FeS₂)
Jasper with Hematite (Red Jasper)
Silicon Dioxide with Iron Oxide (SiO2 and Fe2O3)
Blue Dyed Agate Geode
Chalcedony (cryptocrystalline Quartz), SiO2
Man-made Green Quartz (Lab-grown or Treated)
Silicon Dioxide (SiO2) with artificial coloration
Pyrite in Shale
Iron Disulfide (FeS2)
Quartzite (Water-worn Pebble)
Metamorphosed Quartz Sandstone (SiO2)
Quartzite
Quartzite (primarily Silicon Dioxide, SiO2)
Ruby
Corundum (Al2O3 with Chromium traces)
Yellow Quartzite (River Pebble)
Quartzite (primarily Silicon Dioxide, SiO2)
Sandstone
Clastic Sedimentary Rock (composed mostly of SiO2)
Halite (Rock Salt)
Halite; NaCl (Sodium Chloride)
Sandstone (with carbonaceous plant fragments)
Arenite (composed primarily of SiO2)
Sandstone
Arenite (primarily composed of SiO2)
Shale
Fissile Siliciclastic Sedimentary Rock
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Chert
Silicon dioxide (SiO2)
Banded Agate (specifically Carnelian Agate color)
Silicon Dioxide (SiO2) - variety of Chalcedony
Blue Agate (Dyed Chalcedony)
Silicon Dioxide (SiO2)
Amethyst
Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities
Amber
Succinite (a variety of fossilized tree resin); chemical formula appx. C10H16O
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Iron Oxide cement)