Ruby (Corundum)
Al2O3 (Aluminium oxide with Chromium impurities)
Category
Browse mineral, often found as a rock (metamorphic) specimens identified by the Rock Identifier community.
Ruby (Corundum)
Al2O3 (Aluminium oxide with Chromium impurities)
Tourmaline (Multi-colored)
Complex Borosilicate (Na,Ca)(Li,Mg,Al,Fe)3Al6(BO3)3Si6O18(OH)4
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
Iron Slag (Industrial Byproduct)
Anthropogenic Vitrification Product/Ferrous Slag
Granite or Pegmatite in host rock
Granitoid / Felsic Intrusive Rock
Orange Calcite
Calcium Carbonate (CaCO3)
Citrine Quartz
Silicon Dioxide (SiO2)
Quartz / Citrine Quartz
Silicon Dioxide (SiO2)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Unakite
Epidotized Granite
Desert Varnish on Sandstone
Ferromanganese coating on Quartz Arenite
Lapis Lazuli
Lazurite (primary mineral component), (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
Quartz (Clear/White)
Silicon Dioxide (SiO2)
Slate
Slate (a fine-grained, foliated metamorphic rock). Mineral composition: Primarily composed of mica minerals (muscovite, chlorite, sericite) and quartz, with minor amounts of hematite, pyrite, and other accessory minerals.
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
Smoky Quartz
Silicon Dioxide (SiO₂)
Quartz / Iron-Stained Quartz
Silicon Dioxide (SiO2) with iron oxide inclusions/staining
Sunstone
Aventurine Feldspar (Plagioclase Feldspar with inclusions)
Granite Gneiss
Felsic Gneiss
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Druzy Quartz Geode (Vug)
Silicon Dioxide (SiO2)
Amazonite
Microcline (variety Amazonite) - K(AlSi3O8)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
River Stone (likely Siltstone or fine-grained Sandstone)
Clastic Sedimentary Rock (Lithic Wacke / Siltstone)
Gneiss (with Quartz and Biotite Mica)
Gneiss
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Quartz (Druzy/Macro-crystalline)
Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Pyrite
Iron Disulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Diorite
Intermediate plutonic igneous rock
Clear Quartz
Silicon Dioxide (SiO2)
Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Pyrite
Iron Sulfide (FeS2)
Smoky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz (Crystal Cluster)
Silicon Dioxide (SiO2) - Quartz Variety
Citrine
Silicon Dioxide (SiO2)
Sandstone (Graywacke)
Arenite / Graywacke (SiO2 with lithic fragments)
Yellow Jasper
Jasper (Silica-rich Microcrystalline Quartz, SiO2)
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)