Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse gemstone specimens identified by the Rock Identifier community.
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Labradorite (Feldspar)
Labradorite: (Ca,Na)(Al,Si)4O8
Yellow Quartz (Iron-Stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Epidosite
Epidosite (predominantly Epidote {Ca2Al2Fe3+Si3O12(OH)} and Quartz {SiO2})
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2 with Fe2O3 inclusions)
Dumortierite Quartz (Blue Quartz)
Al7BO3(SiO4)3O3 (Aluminum Boro-silicate included in Quartz)
Prehnite
Prehnite Ca2Al2Si3O10(OH)2
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (Nodule)
Chert (Microcrystalline Quartz, SiO2)
Chert (Iron-stained)
Chert (SiO2)
Quartz Vein in Sedimentary Matrix
Silicon Dioxide (SiO2) with host rock
Pink Tourmaline in Quartz Matrix
Elbaite (Na(Li,Al)3Al6(Si6O18)(BO3)3(OH)4) in Quartz (SiO2)
Black Star Diopside
Diopside (CaMgSi2O6) with asterism
Smoky Quartz (with possible Feldspar inclusions)
Silicon Dioxide (SiO2)
Pyrite (on the right) and Magnetite or Hematite (on the left)
Iron Sulfide (FeS2) and Iron Oxide (Fe3O4 or Fe2O3)
Chert (specifically Tan/Gray Chert)
Microcrystalline quartz (SiO2)
Jasper (specifically Red Jasper or Iron-stained Chert)
Silicon dioxide (SiO2) with iron oxide inclusions
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
Magnetite
Magnetite (Iron(II,III) oxide, Fe3O4)
Blue Sapphire
Corundum (Al2O3)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Green Aventurine
Aventurine (a variety of Quartz, SiO2)
Labradorite
Labradorite ((Ca, Na)(Al, Si)4O8)
Amethyst
Silicon Dioxide (SiO2 with iron impurities)
Blue Sapphire
Corundum (Al2O3)
Quartz (Milky or White Quartz)
Silicon Dioxide (SiO2)
Obsidian
Volcanic Glass (SiO2 dominant)
Dolomite on Prehnite (Saddle-shaped Dolomite)
Dolomite [CaMg(CO3)2] on Prehnite [Ca2Al(AlSi3O10)(OH)2]
Pyrite
Iron Sulfide (FeS2)
Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Amazonite
Triklinic Potassium Feldspar (KAlSi3O8)
Rough Emerald/Green Beryl
Beryl (Be3Al2(SiO3)6) with trace amounts of Chromium or Vanadium
Obsidian
Volcanic Glass (SiO2, usually >70% silica content)
Pink Garnet in Matrix
Grossular or Almandine Garnet (X3Y2(SiO4)3)
Amber
Succinite (approximate formula C10H16O)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Carnelian
Carnelian (a variety of Chalcedony), SiO2 (Silicon Dioxide)
Carnelian
Cryptocrystalline Quartz (SiO2 with iron oxide impurities)