Smoky Quartz
Silicon Dioxide (SiO₂)
Category
Browse metamorphic or sedimentary depending on local grade specimens identified by the Rock Identifier community.
Smoky Quartz
Silicon Dioxide (SiO₂)
Druzy Quartz on Matrix (likely Limestone or Sandstone)
Silicon Dioxide (SiO2) with various trace impurities
Blue Kyanite
Kyanite (Al2SiO5)
Bicolor Tanzanite
Zoisite (Ca2Al3(SiO4)3(OH))
Tiger's Eye (Mineral Collection)
Tiger's Eye (SiO2 with crocidolite inclusions)
Quartzite
Quartzite (primarily SiO2)
Rough Sapphire
Corundum (Al2O3)
Ruby
Corundum (Aluminum Oxide with Chromium), Al2O3:Cr
Travertine
Terrestrial Sedimentary Form of Calcium Carbonate (CaCO3)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals like Antigorite, Lizardite, and Chrysotile)
Blue Sapphire
Corundum (Al2O3 with trace Titanium and Iron)
Schist
Mica Schist (primarily Muscovite and Quartz)
Green Calcite
Calcium Carbonate (CaCO3)
Asphalt
Asphalt concrete (engineered material, not a naturally occurring rock/mineral in this form)
Conglomerate
Conglomerate (clastic sedimentary rock)
Fluorite-Gedrite in Quartz (Schist)
Fluorite (CaF2) with Gedrite in Quartz/Feldspar Matrix
Ruby in Fuchsite (often confused with Ruby in Zoisite)
Corundum (Al2O3) in Chromium-rich Muscovite (KAl2(AlSi3O10)(OH)2)
Jadeite Jade
NaAlSi2O6 (Sodium Aluminum Silicate)
Black Tourmaline
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
Quartzite River Rock with Dendrites
Metamorphosed Quartz-rich Sandstone with Manganese Oxide (MnO2) inclusions
Quartzite
Quartzite (SiO2)
Schist
Schist (primarily mica-schist)
Iceland Spar (Optical Calcite)
Calcite (Calcium Carbonate, CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Black Diamond / Black Sapphire
Carbon (C) or Corundum (Al2O3)
Geode with Quartz and Chalcedony
Silicon Dioxide (SiO2)
Chalk
Calcium Carbonate (CaCO3)
Bauxite (Pisolitic Bauxite)
Bauxite (mixture of Hydrous Aluminum Oxides)
Crinoid and Coral Fossils in Limestone
Fossiliferous Limestone with Rugosa (order) and Crinoidea (class)
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (Calcium Carbonate, CaCO3)
Sandstone Concretion
Clastic sedimentary rock (primarily Quartz SiO2)
Jasper (Petrified Wood Variety)
Silicon Dioxide (SiO2)
Chert (Yellow Jasper variant)
Silicon Dioxide (SiO2)
Aventurine (likely Green Aventurine)
Aventurine (a variety of quartz, SiO₂, with common inclusions of fuchsite)
Peacock Ore
Bornite (Cu5FeS4)
Red Jasper (Chert)
Silicon dioxide (SiO2) with iron oxide inclusions
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Gossan (Iron Hat)
Limonitic Gossan (Fe-oxide/hydroxide complex)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
Limestone (Fossiliferous)
Calcium Carbonate (CaCO3)
Ruby
Corundum (Al2O3 with Chromium traces)