Granite
Granite (Mainly Quartz SiO2, K-Feldspar KAlSi3O8, and Plagioclase)
Category
Browse man made object (metal alloy) specimens identified by the Rock Identifier community.
Granite
Granite (Mainly Quartz SiO2, K-Feldspar KAlSi3O8, and Plagioclase)
Limestone
Calcium Carbonate (CaCO3)
Sandstone (River Cobble)
Clastic sedimentary rock (primarily SiO2 with various lithic fragments)
Quartzite (Iron-stained)
Quartzite (SiO2 with iron oxides)
Quartz (vein quartz)
SiO2 (Silicon Dioxide)
Magnetic Hematite
Magnetized Hematite (an iron oxide mineral, Fe2O3, that has undergone magnetization)
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Serpentinite
Serpentinite (composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite)
Granite
Phaneritic Felsic Igneous Rock
Sandstone Chert/Quartzite
Silicon Dioxide (SiO2) - Sedimentary Sandstone / Orthoquartzite
Chalcedony (Common Opal/Chert variety)
Silicon Dioxide (SiO2)
Beryl (Variety Mix)
Be3Al2(Si6O18)
Milky Quartz
Quartz (SiO2)
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Granite
Granite (Phaneritic Quartz-Feldspar Felsic Rock)
Diamond
Diamond (pure carbon; C)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartzite
Quartzite (primarily composed of SiO O₂)
Banded Iron Formation
Banded Iron Formation (BIF)
Sandstone
Arenite (primarily SiO2)
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Quartz (Rock Crystal)
Quartz (SiO₂ - Silicon Dioxide)
Quartz
Silicon Dioxide (SiO₂)
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Quartz (likely macrocrystalline variety)
Quartz (SiO₂)
Granite
Granite (a common rock type, not a single mineral species)
Quartz
Quartz (SiO₂)
Serpentinite
Serpentinite (a rock composed predominantly of serpentine group minerals)
Garnet (likely Almandine, Pyrope, or a blend)
Garnet group minerals: X3Y2(SiO4)3, where X and Y represent various metal ions (e.g., Almandine: Fe3Al2(SiO4)3, Pyrope: Mg3Al2(SiO4)3)
Sandstone
Sandstone (lithified sand)
Dolomite
Dolomite (CaMg(CO3)2)
Sandstone
Arenite (general term for sandstone)
Sandstone
Quartz Arenite (a common type of sandstone, given the appearance), Arkose, Greywacke (depending on mineralogy)
Quartz
Quartz (SiO₂)
Talc
Talc (Mg₃Si₄O₁₀(OH)₂)
Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)
Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.
Quartz
Quartz (SiO2 - Silicon Dioxide)