Jasper
Microcrystalline Quartz (SiO2)
Category
Browse organic gemstone (sedimentary associations) specimens identified by the Rock Identifier community.
Jasper
Microcrystalline Quartz (SiO2)
White Chalcedony
Silicon Dioxide (SiO2)
Dendritic Agate
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
Tanzanite
Blue Zoisite (Ca2Al3(SiO4)3(OH))
Fluorite
Calcium fluoride (CaF2)
Blue Apatite
Apatite group (Ca5(PO4)3(F,Cl,OH))
Amber (Copal)
Fossilized Tree Resin (C10H16O)
Limonite (Iron Ore)
FeO(OH)·nH2O
Amethyst quartz crystal
Quartz, SiO₂, purple variety (amethyst)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Red Jasper (beads)
SiO₂ (Silicon Dioxide)
Pearls (likely freshwater cultured pearls)
Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin
Red Jasper
Silicon Dioxide (SiO2)
Barite (Desert Rose or Cockscomb variety)
Barium Sulfate (BaSO4)
Prehnite
Ca2Al(AlSi3O10)(OH)2
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Gemstones (Emerald and Yellow Topaz or Citrine)
Beryl (Be3Al2Si6O18) and Quartz (SiO2) or Topaz (Al2SiO4(F,OH)2)
Epidote (Greenstone)
Calcium aluminum iron silicate hydroxide Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)
Amber
Succinicum (Organic Gemstone - Resinite)
Likely weathered quartz-rich stone
Indeterminate; possibly quartz-bearing granite or milky quartz
Red Jasper with Chalcedony Banding
Microcrystalline Quartz (SiO2) with Hematite inclusions
Flint
SiO2 (Cryptocrystalline Quartz / Chert)
Citrine Quartz (or Heat-Treated Amethyst / Smoky Quartz)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Nephrite Jade
Tremolite-Actinolite solid solution Ca2(Mg,Fe)5Si8O22(OH)2
Amber (Copal)
Succiniferous Resin
Mixed Mineral Collection (with Quartz, Beryl, and host rock)
Silicon Dioxide (Quartz), Be3Al2Si6O18 (Beryl), and associated Schist/Pegmatite
Amber
Succinite (organic gemstone, approx. C10H16O)
Turquoise
Hydrous phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Morganite
Beryl (Be3Al2Si6O18 with Mn)
Green Chert
Microcrystalline Quartz (SiO2)
Ferruginous Sandstone (with Pyrite/Gold associations)
Ferruginous Arenite (SiO2 + Fe2O3)
Malachite
Copper(II) carbonate hydroxide [Cu2CO3(OH)2]
Blue-green copper mineral specimen, likely chrysocolla-bearing rock
Chrysocolla, hydrated copper phyllosilicate: approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O; possibly mixed with malachite or chrysocolla matrix
Green Jasper
Microcrystalline Quartz (SiO2) with mineral inclusions
Chert (Jasper)
Silicon Dioxide (SiO2)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Amber
Organic gemstone (Succinite is common if from the Baltic)
Sodalite
Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)
Epidote
Epidote (Ca2(Al,Fe)3(SiO4)3(OH))
Natural freshwater pearls
Pearl (nacreous calcium carbonate; chiefly aragonite, CaCO₃)