River Stone (likely Basalt or Chert)
Silicon Dioxide (SiO2) for chert or Mafic Extrusive Rock for basalt
Category
Browse synthetic or natural fiber specimens identified by the Rock Identifier community.
River Stone (likely Basalt or Chert)
Silicon Dioxide (SiO2) for chert or Mafic Extrusive Rock for basalt
Sandstone
Arenite (SiO2 primarily)
Shiva Lingam
Cryptocrystalline Quartz (Jasper/Chalcedony) with Iron Oxide inclusions
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
Dyed Chalcedony (Agate)
Silicon Dioxide (SiO2) with artificial pigment
Limonite/Hematite Ironstone
Goethite-rich Ironstone (FeO(OH) · nH2O)
Sandstone
Arenite (SiO2 primarily)
Shale
Fissile Mudstone
Tiger's Eye (dark/grey variant)
Pseudomorph of Quartz after Crocidolite (SiO2)
Banded Agate
Cryptocrystalline Silica (SiO2)
Black Onyx
Silicon Dioxide (SiO2) with parallel banding
Red Sandstone (Iron-rich)
Arenite (with Hematite cement)
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (SiO2 dominated)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
Druzy Quartz
Silicon Dioxide (SiO2)
Limestone with Gastropod Fossil
Sedimentary Calcium Carbonate (CaCO3) with Gastropoda inclusion
Pumice
Pumice (Vesicular Rhyolite/Andesite)
Pearl (Biogenic)
Nacre / Calcium Carbonate (CaCO3)
Chalcedony (Agate and Jasper Pebbles)
Microcrystalline Quartz (SiO2)
Amethyst (Tumbled)
Amethyst (Silicon Dioxide, SiO2 + Fe4+)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Bismuth Crystal
Bismuth (Bi)
Shale
Laminated Mudstone (Shale)
Limonite with Hematite
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Red Sandstone
Arenite (predominantly Quartz with Hematite cementation)
Sandstone (specifically Arkose or Ferruginous Sandstone)
Sandstone (SiO2 predominant)
Sandstone (with prominent jointing/fractures)
Arenite (composed primarily of SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Slate
Slate (Low-grade foliated metamorphic rock)
Yellow Sapphire (Corundum)
Corundum (Aluminum Oxide, Al2O3)
Sandstone
Arenite (SiO2 based)
Smoky Quartz and Orthoclase Feldspar
Granitic Pegmatite (SiO2 + KAlSi3O8)
Yellow Quartz Pebble
SiO2 (Silicon Dioxide)
Sandstone (Quartz-rich)
Sandstone (SiO2 dominated)
Shale
Shale (Lutite)
Sandstone
Arenite
Sandstone
Arenite
Shale
Lutaceous sedimentary rock
Slag
Anthropogenic glassy silicate
Aura Amethyst (Dyed/Coated)
Titanium-treated Silicon Dioxide (SiO2)
Citrine Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)