Basalt
Basalt (composition of plagioclase, pyroxene, and olivine)
Category
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Basalt
Basalt (composition of plagioclase, pyroxene, and olivine)
Granite
Phaneritic Plutonic Rock (primarily Quartz, Feldspar, and Mica/Amphibole)
Sandstone (Ferruginous)
Arenite (with iron oxide cement)
Quartz / Iron-Stained Quartz
Silicon Dioxide (SiO2) with iron oxide inclusions/staining
Diorite
Diorite (Intermediate intrusive igneous rock)
Emerald
Beryl (Be₃Al₂Si₆O₁₈), specifically the green variety colored by trace amounts of chromium or vanadium.
Gneiss
Gneiss (High-grade Metamorphic Rock)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
Sodalite
Na8(Al6Si6O24)Cl2
Sodalite
Sodalite [Na8(Al6Si6O24)Cl2]
Quartz (Druzy on Matrix)
Silicon Dioxide (SiO2)
Granite
Granite (a felsic intrusive igneous rock)
Granite Pebble
Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Granitic Pegmatite
Granite Pegmatite (coarse-grained intrusive igneous rock)
Aventurine
Quartz (SiO2) with inclusions of Fuchsite
Greyling Sandstone / Greywacke
Lithic Wacke (SiO2 + diverse mineral fragments)
Sandstone Clast
Arenite (primarily SiO2)
White Marble
Calcite-rich Metasomatized Carbonate (CaCO3)
Rhodonite
Rhodonite (MnSiO3)
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Quartz (Milky/Yellowish Pebble)
Silicon Dioxide (SiO2)
Granite Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Carved Mottled Greenish-Yellow Crystal/Glass Object
Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.
Granite
Phaneritic Igneous Rock (composed mostly of Quartz, Alkali Feldspar, and Plagioclase)
Serpentine, likely a variety of Chrysoprase (green chalcedony) or a similar translucent green mineral.
Serpentine Group Minerals (e.g., Antigorite, Lizardite) or Chalcedony (SiO2) with nickel impurities for Chrysoprase green.
Diamond (Lesedi La Rona specimen)
Diamond (Pure Carbon, C)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz with Iron Staining
Silicon Dioxide (SiO2) with Limonite/Hematite inclusions
Rough Diamond
Diamond (Native Carbon, C)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Dendritic Agate (specifically Orange/Tumbled)
Silicon Dioxide (SiO2) with Oxide Inclusions
Hypersthene
Hypersthene (formula: (Mg,Fe)SiO3)
Blue Cracked Quartz (Dyed Fire Crackle Quartz)
Silicon Dioxide (SiO2) with synthetic dye
Caribbean Calcite
Calcium Carbonate with Argonite (CaCO3)
Milk Quartz (Common White Quartz)
Quartz (Silicon Dioxide, SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Garden Quartz (Lodalite)
Silicon Dioxide (SiO2) with various inclusions
Ruby
Corundum (Al2O3 with Chromium traces)
Rough Diamond
Diamond (pure Carbon, C)
Amethyst (Chevron or Banded variety)
Silicon Dioxide with Iron impurities (SiO2)
Rough Diamond
Diamond (pure carbon / C)
Quartz with Iron Staining
Silicon Dioxide (SiO2)