Chrysoprase
Chrysoprase (a variety of Chalcedony, SiO₂)
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Chrysoprase
Chrysoprase (a variety of Chalcedony, SiO₂)
Green Calcite
Calcite (CaCO3)
Olivine (Peridot in gem form)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Sandstone (Ferruginous)
Arenite with Iron Oxide (Fe2O3) cement
Sandstone (Micaceous)
Arenite (composed primarily of SiO2)
Sandstone (Water-worn Pebble)
Clastic Sedimentary Rock (primarily SiO2)
Turquoise
Hydrous phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Beryl (Emerald Variety)
Beryllium aluminum silicate (Be3Al2(SiO3)6) with chromium/vanadium traces
Moissanite
Silicon Carbide (SiC)
Quartz Geode
Silicon Dioxide (SiO2) in Host Rock
Orange Calcite
Calcium Carbonate (CaCO3)
Red Jasper (Polished)
Jasper (Iron-rich Microcrystalline Quartz, SiO2)
Geode (Chert or Quartz Nodule)
Silicon Dioxide (SiO2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Halite (Rock Salt)
Halite (Sodium Chloride, NaCl)
Orange Calcite (Cleavage Rhomb)
Calcite (Calcium Carbonate, CaCO3)
Manganese Ore (Psilomelane/Pyrolusite)
Psilomelane ((Ba,H2O)2Mn5O10) and Pyrolusite (MnO2)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Green Opal
Hydrated Silica (SiO2·nH2O)
Pearl (Biogenic)
Nacre / Calcium Carbonate (CaCO3)
Amethyst
Silicon Dioxide (SiO2) with trace Iron (Fe) impurities
Citrine
Silicon dioxide (SiO2)
Quartz (likely a clear or rock crystal variety)
Quartz (SiO2 - Silicon Dioxide)
Red Jasper
Silicon Dioxide (SiO2) with Iron impurities
Rhodonite in Matrix
Rhodonite (Manganese Silicate) - (Mn2+,Fe2+,Mg,Ca)SiO3
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Rhodonite (Manganese Silicate), (Mn,Fe,Mg,Ca)SiO3
Moldavite
Tektite (Impact Glass), ~80% SiO2 + Al2O3
Unakite
Epidotized Granite
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2 + Fe2O3)
Fire Opal (in matrix)
Hydrated Silica (SiO2·nH2O)
Serpentine
Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
Sphalerite in Matrix (Polished Point)
Zinc sulfide (Zn,Fe)S
Jasper
Silicon Dioxide (SiO2)
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in calcitic matrix
Sunstone
Plagioclase feldspar (with Copper or Hematite inclusions)
Sandstone (with ripple marks)
Arenite / Quartz Sandstone
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium), CuAl6(PO4)4(OH)8·4H2O
Quartz (Crystal/Druzy Quartz)
Quartz (SiO₂)
Chalk
CaCO3 (primarily Calcium Carbonate), biogenic sedimentary rock
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Sandstone
Arenite (Sedimentary rock composed of sand-sized grains, primarily SiO2)