Rutilated Quartz
SiO2 with TiO2 inclusions
Category
Browse mineral like byproduct (often mistaken for igneous rock or meteorite) specimens identified by the Rock Identifier community.
Rutilated Quartz
SiO2 with TiO2 inclusions
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals like Antigorite, Lizardite, and Chrysotile)
White Quartz (Milky Quartz)
Quartz (Silicon Dioxide - SiO2)
Pyrite
Iron Sulfide (FeS2)
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Quartz (Milky/Gravel variety)
Silicon Dioxide (SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Yellow Quartz (Citrinated Quartz)
Silicon Dioxide (SiO2)
Blue Lace Agate (Tumbled)
Silicon Dioxide (SiO2)
Ironstone (likely siderite or goethite-rich siltstone)
Ferruginous Siltstone
Greenstone (metamorphosed basalt)
Greenschist / Meta-basalt
Quartz
Silicon Dioxide (SiO₂)
Pink Chalcedony (Agate/Jasper blend)
Silicon Dioxide (SiO₂)
Greenstone (Greywacke or Nephrite Jade variant)
Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)
Magnetite (potentially Hematite-rich)
Magnetite (Fe3O4)
Basalt with Iron Oxidation (Lattice/Veined)
Mafic Volcanic Rock (principally Plagioclase and Pyroxene)
Greisen (Quartz-Muscovite-Turretine Rock)
Greisen
Vesicular Basalt
Extrusive Mafic Igneous Rock
Sandstone
Arenite (primarily SiO2 - Silicon Dioxide)
Bauxite
Bauxite (principal ore of aluminum, primarily Al(OH)3)
Smoky Quartz
Silicon Dioxide (SiO2)
Red Granite
Granite (Felsic Plutonic Rock)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Basalt
Basalt (Mafic volcanic rock)
Granite
Phaneritic Plutonic Felsic Rock
Obsidian / Volcanic Glass
Obsidian (principally SiO2, usually 70% or more)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, Mg3Si2O5(OH)4)
Basalt
Basalt (High-iron/magnesium silicate rock)
Sandstone (Quartz Sandstone)
Arenite (primarily SiO2)
Granite Pebble (Salt and Pepper Granite)
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Biotite/Amphibole)
Dendritic Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Quartzite
Quartzite (primarily SiO2)
Sandstone (Ferruginous)
Arenite (Fe-bearing Clastic Sedimentary Rock)
Vesicular Basalt
Aphanitic Mafic Igneous Rock (with Vesicular Texture)
Red Garnet (Pyrope or Almandine)
Garnet Group (A3B2(SiO4)3)
Basalt
Basalt (Mafic volcanic rock)
Serpentine (Nephrite-like River Cobble)
Serpentinite (Hydrous Magnesium Iron Silicate)
Basalt
Extrusive mafic igneous rock
Pumice
Vesicular volcanic glass (Amorphous silica mixed with various oxides)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Herkimer Diamond
Quartz (SiO2)