Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
Category
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
Schist
Mica Schist
Quartz (Tumbled)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Quartz (Milky or Cloudy variety)
Quartz (Silicon Dioxide, SiO2)
Quartz Pebble
Silicon dioxide (SiO2)
Quartz Pebble (with Iron Inclusions)
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)
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.
Schist
Mica Schist (primarily consisting of muscovite KAl2(AlSi3O10)(OH)2 or biotite K(Mg,Fe)3(AlSi3O10)(OH)2)
K2 Azurite Granite / K2 Stone
Granite (igneous rock) with Azurite inclusions (mineral)
Goethite (Iron Ore)
Goethite (FeO(OH))
Serpentinite
Serpentinite (composed primarily of serpentine-group minerals like antigorite, chrysotile, and lizardite; chemical formula varies but generally Mg3Si2O5(OH)4)
Dendritic Agate
Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)
Aquamarine
Beryl (Be3Al2Si6O18)
Pyrite
Iron Sulfide (FeS2)
Pyrite
Iron Disulfide (FeS2)
Magnetite Orthorthotropic Rock
Magnetite (Fe3O4)
Mixed Gemstone Collection
SiO2 (Quartz varieties) and Biogenic CaCO3 (Nacre)
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Sandstone with Quartz Vein
Arenite with SiO2 intrusion
Gneiss
Gneiss (High-grade metamorphic rock)
Turquoise (Rough Specimens)
Hydrous phosphate of copper and aluminium - CuAl6(PO4)4(OH)8·4H2O
Banded Rhyolite (likely Green Jasper/Agate variety)
Silicon Dioxide (SiO2) with mineral inclusions