Sandstone
Clastic sedimentary rock (primarily SiO2)
Category
Browse mineral health specimens identified by the Rock Identifier community.
Sandstone
Clastic sedimentary rock (primarily SiO2)
Pyrite
Iron Disulfide (FeS2)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Hematite
Iron (III) Oxide (Fe2O3)
Caribbean Calcite
Calcium Carbonate (CaCO3) with Aragonite (CaCO3)
Schist
Mica Schist
Gneiss (Augen Gneiss)
Augen Gneiss
Quartz Vein in Host Rock (often Granite or Schist)
Silicon Dioxide (SiO2) within host matrix
Crushed Stone / Gravel
Aggregatus saxum (variable mineral composition)
Hypersthene
Hypersthene ((Mg,Fe)SiO₃)
Quartz Vein in Rhyolite
Silicon Dioxide (SiO2) in extrusive igneous rock
Chert with Quartz Druzy
Microcrystalline Quartz (SiO2) with Drusy Quartz Coating
Yellow Quartz
Silicon Dioxide (SiO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Rose Quartz
SiO2 (Silicon Dioxide)
Quartz (Milky Quartz/Citrine Type)
Silicon Dioxide (SiO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Yellow Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Blue Quartzite
Quartzite (mostly SiO2 with mineral inclusions)
Shale
Fissile mudstone (primarily clay minerals and silt-sized quartz)
Smoky Quartz
Quartz (Silicon Dioxide), Formula: SiO2
Rose Quartz
Silicon Dioxide (SiO2) with traces of titanium, iron, or manganese
Fuchsite
K(Al,Cr)2(AlSi3O10)(OH)2 (Chromium-rich Muscovite)
Milky Quartz
Silicon Dioxide (SiO2)
Schist
Mica Schist
Epidote
Epidote Group (e.g., Clinozoisite, Epidote, Piemontite), Epidote formula: Ca2(Al,Fe)3(SiO4)3(OH)
Granite
Phaneritic Igneous Rock (composed mostly of Quartz, Feldspar, and Mica)
Bornite
Bornite (Cu5FeS4)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Druzy Quartz)
Silicon Dioxide (SiO2)
Citrine
Silicon Dioxide (SiO₂)
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Garnet (likely Almandine)
Almandine Garnet, Fe3Al2(SiO4)3
Quartz Geode
Crystalline Quartz (Silicon Dioxide, SiO2)
Schist
Mica Schist
Granite Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Pegmatite (Granitic)
Granitic Pegmatite
Schist
Mica Schist
Quartz with Iron Inclusions
Silicon Dioxide (SiO2) with Hematite/Limonite