Corundum (Sapphire)
Corundum (Al2O3)
Category
Browse sedimentary like (industrial composite) specimens identified by the Rock Identifier community.
Corundum (Sapphire)
Corundum (Al2O3)
Anthracite Coal
Anthracite (Carbon-based solid)
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
Basalt
Extrusive mafic igneous rock
Rough Diamond
Native Carbon (C)
Basalt
Mafic Igneous Rock
Quartzite (Beach Pebble)
Quartzite (primarily SiO2)
Ferruginous Quartz
Quartz with Iron Oxide inclusions (SiO2 + Fe2O3)
Granitic Pegmatite
Pegmatite
Olivine in Basalt matrix
Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)
Granodiorite Pebble
Granodiorite
Granodiorite (containing Biotite and Quartz)
Granodiorite (Plagioclase-rich phaneritic intrusive rock)
Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Riverstone (Sandstone or Quartzite)
Sedimentary Rock (likely Arenite)
White Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Slag
Anthropogenic Vitreous Silica/Iron oxides
Milky Quartz
Quartz (SiO2) with iron staining
Quartzite with inclusions
Metamorphic Rock (Mainly SiO2)
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt
Cubic Zirconia
Zirconium Dioxide (ZrO2)
Schist
Mica Schist
Blue Calcite
Calcium Carbonate (CaCO3)
Milky Quartz with Talc / Serpentine
Silicon Dioxide (SiO2) with Mg3Si4O10(OH)2
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide - SiO2)
Basalt with Secondary Mineralization (Likely Zeolites or Calcite)
Aphanitic mafic volcanic rock with secondary mineral inclusions (e.g., CaAl2Si3O10·3H2O for Scolecite)
Tumbled amber
Amber (fossilized plant resin), chiefly polymerized diterpenoid resin
Diamond
Carbon (C)
Copper Ore (likely Chalcopyrite in Matrix)
Chalcopyrite (CuFeS2)
Granitic Pegmatite
Pegmatite containing Quartz, Feldspar, and Muscovite mica
Gray Agate
Chalcedony (Silicon Dioxide, SiO2)
Massive Quartz with Host Rock
Silicon Dioxide (SiO2)
Diamond (Pear Cut)
Carbon (C)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Quartz (specifically Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Quartz with Mica inclusion
Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions
Quartzite
Quartzite (SiO₂)
Schist (Micaceous)
Mica Schist
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese