Granite (Weathered)
Phaneritic Plutonic Rock (primarily Quartz, Feldspar, and Mica)
Category
Browse igneous, sedimentary, or metamorphic (mineral based) specimens identified by the Rock Identifier community.
Granite (Weathered)
Phaneritic Plutonic Rock (primarily Quartz, Feldspar, and Mica)
Granitic Pegmatite
Phaneritic Granite with Potassium Feldspar (KAlSi3O8), Quartz (SiO2), and Plagioclase
Lapis Lazuli
Complex mixture of minerals, primarily Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2
Chalcedony (Agate/Quartz)
Silicon Dioxide (SiO2)
Schist
Schist (various mineral compositions)
Opalite
Synthetic Glass (typically Silica/Magnesium based with metal additives)
Basalt Pebble with Epidote/Olivine
Vitreous Basalt (SiO2 with Ca/Mg/Fe silicates)
Pink Granite (Potassium-rich Granite)
Phaneritic Felsic Igneous Rock (primarily SiO2, Al2O3, K2O)
Graywacke
Graywacke Sandstone
Sandstone (Quartzose type)
Arenite (primarily SiO2)
Basalt (with possible Olivine inclusions)
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Orca Agate
Chalcedony (Microcrystalline Quartz, SiO2)
Quartz with Mica inclusions (Gold-colored Mica)
Silicon Dioxide (SiO2) with Potassium Aluminum Silicate (Phlogopite/Muscovite) inclusions
Milky Quartz
Silicon Dioxide (SiO2)
Marble
Recrystallized Carbonate Rock (CaCO3)
Schist
Schist
Diorite
Diorite (Intermediate intrusive igneous rock)
Schist
Mica Schist
Sandstone (likely Arkosic)
Clastic Sedimentary Rock (Sandstone)
Tufa (Limestone)
Calcareous Tufa (CaCO3)
Red Sandstone
Arenite (Ferruginous Sandstone)
Granodiorite
Granodiorite (phaneritic intrusive igneous rock)
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)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Smoky Quartz
Silicon Dioxide (SiO2)
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
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)
Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Sunstone
Aventurine Feldspar (Plagioclase Feldspar with inclusions)
Milky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Smoky Quartz (SiO2: Silicon Dioxide)
Calcite in Matrix
Calcium Carbonate (CaCO3)
Citrine
Silicon Dioxide (SiO2) - Macrocrystalline Quartz variety
Sandstone (with Chert/Quartzite)
Arenite (primarily SiO2)
Snowflake Obsidian (Tumbled)
Obsidian with Cristobalite inclusions
Amber
Succinite (Carbon-based organic compound; approximate formula C10H16O)
Sandstone (likely with Borings or Vesicular Basalt)
Clastic Sedimentary Rock (Sandstone)