Granite
Granite (a plutonic igneous rock composed of quartz, feldspar, and mica)
Category
Browse mineral like biological tissue specimens identified by the Rock Identifier community.
Granite
Granite (a plutonic igneous rock composed of quartz, feldspar, and mica)
Bauxite
Hydrated Aluminum Oxides (primarily Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Diaspore α-AlO(OH))
Orbicular Jasper (Ocean Jasper variant)
Silicon Dioxide (SiO2) with iron oxide inclusions
Sandstone (Ferruginous)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)
Sandstone (Ferruginous)
Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)
Quartzite with Chlorite/Epidote
Metamorphosed Quartzite (SiO2)
Snowflake Obsidian
Spherulitic Obsidian (SiO2 + impurities)
Green Calcite
Calcium Carbonate (CaCO3)
Prehnite
Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate hydroxide)
Slag Glass
Amorphous Silica / Glass Slag
Gold Nugget
Native Gold (Au)
Ferruginous Quartz
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)
Agate
Silicon dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Dzi Bead (Etched Chalcedony)
Cryptocrystalline Quartz (SiO2) with chemical etching
Smoky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) - Variety: Chalcedony
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Blue Kyanite in Quartz
Kyanite (Al2SiO5)
Satin Spar (Selenite)
Gypsum (CaSO4·2H2O)
Purple Chalcedony (likely dyed Agate)
Silicon Dioxide (SiO2)
Smoky Quartz
Smoky Quartz (SiO2)
Beryl (Emerald Variety)
Beryllium aluminum silicate (Be3Al2(SiO3)6) with chromium/vanadium traces
River Stone (likely Siltstone or fine-grained Sandstone)
Clastic Sedimentary Rock (Lithic Wacke / Siltstone)
Yellow Quartzite (Beach Pebble)
Quartzite (primarily SiO2)
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Arsenic (Native)
Arsenic (As)
Rose Quartz
Rose Quartz (SiO2 with traces of Ti, Fe, or Mn)
Gold in Quartz Matrix
Native Gold (Au) with Quartz (SiO2) and Slate/Shale
Note: Item is not a geological specimen
Guitar Components (Steel, Nickel, Plastic, Wood)
Snowflake Obsidian
Spherulitic Obsidian (Amorphous volcanic glass with Phenocrysts of Cristobalite)
Olivine
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
Lepidolite with Rubellite Tourmaline
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite mica)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Chalcedony Nodule in Matrix
Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Granite (specifically Pink or Alkali Feldspar Granite)
Felsic Plutonic Rock (primarily SiO2 with KAlSi3O8)
Granite
Granitoid (composition typically SiO2, Al2O3, K2O, Na2O)
Sandstone
Clastic Sedimentary Rock (composed mostly of SiO2)
Ferruginous Sandstone
Sandstone (rich in iron oxides/hydroxides)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)