Sandstone (Ferruginous)
Arenite with Iron-oxide inclusions (SiO2 primarily)
Category
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Sandstone (Ferruginous)
Arenite with Iron-oxide inclusions (SiO2 primarily)
Limonite (Iron Ore)
Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)
Azurite-Malachite (often a mixed specimen)
Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2(CO3)(OH)2. The specimen appears to be a natural mixture or intergrowth of these two minerals.
Amphibolite
Amphibolite
Native Copper with Malachite and Chrysocolla
Native Copper (Cu) with Malachite [Cu2CO3(OH)2] and Chrysocolla [(Cu,Al)2H2Si2O5(OH)4·nH2O]
Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
Granite
Granite (composed mainly of Quartz, Feldspar, and Mica)
Quartz with Iron Staining
Silicon Dioxide (SiO2) with FeOx inclusions
Assorted Decorative Tumbled Stones (Quartz, Sodalite, Aventurine, Calcite)
Mixed Silicates and Carbonates (SiO2, Na8(Al6Si6O24)Cl2, CaCO3)
Pyrite
Iron Sulfide (FeS2)
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
Pyrite (on Quartz/Host Rock)
Iron Sulfide (FeS₂)
Diorite
Diorite (Intermediate intrusive igneous rock)
Magnetite Orthorthotropic Rock
Magnetite (Fe3O4)
Quartz Druzy on Agate (River Cobble)
Silicon Dioxide (SiO2)
Tiger Iron
Tiger Iron (composite of Tiger's Eye, Red Jasper, and Hematite)
Sandstone (likely Quartzose Sandstone)
Arenite (SiO2 principal composition)
Quartz (Common or Milky)
Silicon Dioxide (SiO2)
Quartz (Grain/Pebble)
Silicon Dioxide (SiO2)
White Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Quartz pebble
Silicon Dioxide (SiO2)
Quartz / Quartzite
Quartz (Silicon Dioxide, SiO2)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Quartz (Iron-stained or Rose variant)
Silicon Dioxide (SiO2)
Blue Quartzite (Dyed)
Silicon Dioxide (SiO2) with inclusions
Quartz Pebble
Silicon Dioxide (SiO2)
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide with impurities (SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Quartz in Matrix (possibly with Biotite or Hornblende)
Quartz (Silicon Dioxide, SiO2) in Granitic Matrix
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Yellow Aventurine (Yellow Quartzite)
Silicon Dioxide (SiO2) with inclusions
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Vesicular Basalt with Lichen
Vesicular Basalt
Limonite (Iron Stone/Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Blue Quartzite (Aventurine variety)
Silicon Dioxide (SiO2) with inclusions of Dumortierite or Magnesio-riebeckite
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Dendritic Agate
Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)
Schist
Mica Schist