Graphite
Graphite (Native Carbon, C)
Category
Browse mixed (sedimentary, igneous, and metamorphic) specimens identified by the Rock Identifier community.
Graphite
Graphite (Native Carbon, C)
Blue Calcite
Calcium Carbonate (CaCO3)
Honey Calcite
Calcium Carbonate (CaCO3)
Pyrite in Matrix (likely Quartz or Coal)
Iron Sulfide (FeS2)
Green Calcite
Calcium Carbonate (CaCO3)
Epidote (or Epidote-rich rock)
Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).
Pyrite
Iron Sulfide (FeS2)
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Strawberry Quartz
Quartz (SiO₂) with Goethite (α-FeO(OH)) and/or Lepidocrocite (γ-FeO(OH)) inclusions
Mica Schist
Mica Schist
Smoky Quartz in Matrix
Silicon dioxide (SiO2) within Pegmatite/Gneiss
Aventurine Quartz
Silicon Dioxide (SiO2) with Fuchsite inclusions
Garnet in Schist (Garnetiferous Micaceous Schist)
Almandine Garnet, Fe3Al2(SiO4)3
Marble
Recrystallized Calcite (CaCO3) or Dolomite (CaMg(CO3)2)
Kyanite (Purple variety)
Kyanite (Al₂SiO₅)
Mica Schist
Mica Schist (primarily Muscovite or Biotite KAl2(AlSi3O10)(OH)2)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
Gneiss (Granitic Gneiss)
Gneiss
Pyrite on Quartz (Fool's Gold in Quartz)
Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)
Blue Sapphire
Corundum (Al2O3 - Aluminum Oxide with Iron and Titanium impurities)
Muscovite Mica (in Quartz/Feldspar Matrix)
Muscovite - KAl2(AlSi3O10)(OH)2
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
Smoky Quartz
SiO2 (Silicon Dioxide with aluminum impurities)
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Emerald
Beryl (Be₃Al₂(SiO₃)₆) with Chromium or Vanadium impurities
Agate
Silicon Dioxide (SiO2) - Chalcedony variety
Quartz Pebble (Citrine-colored or Stained Quartz)
Silicon Dioxide (SiO2)
Blue Sapphire
Corundum (Al2O3) with traces of Iron and Titanium
Smoky Quartz
Silicon Dioxide (SiO2)
Sunstone
Aventurine Feldspar (Plagioclase Feldspar with inclusions)
Quartz (Iron-stained)
Silicon Dioxide (SiO2) with Iron Oxide impurities
Milky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Smoky Quartz (SiO2: Silicon Dioxide)
Quartzite (River Stone)
Quartzite (mainly SiO2 with iron oxide staining)
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
Quartzite Pebble (River Rock)
Quartzite (SiO2)
Quartzite Pebble (River Rock)
Quartzite (mainly SiO2)