Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Category
Browse organic gemstone (sedimentary associations) specimens identified by the Rock Identifier community.
Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Hematite Nodular Concretion
Iron(III) oxide (Fe2O3)
Quartz (Milky/Rose variety)
Silicon Dioxide (SiO2)
Shale
Shale
Chert (specifically Tan/Brown Chert)
Chert (SiO2)
Botryoidal Chalcedony
Silicon Dioxide (SiO2)
Quartz
Silicon dioxide (SiO2)
Turquoise (Rough)
Hydrated phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Petrified Wood
Silicified Wood (SiO2)
Dalmation Stone
Peralkaline Rock (mixed silicate minerals)
Ironstone Concretion / Limonite Node
Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)
Orange Calcite (Mexican Onyx)
Calcium Carbonate (CaCO3)
Turquoise in Matrix
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Jasper (likely Brown or Brecciated)
Jasper (Silicon Dioxide, SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Agate (or Chalcedony)
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2)
Chert (specifically Jasper or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Septarian Nodule
Septarian Concretion
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Precious Opal
Hydrated Silica (SiO2·nH2O)
Red Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
Geode (Calcite or Quartz)
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)
Septarian Nodule
Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)
Jasper
Jasper (Silicon Dioxide, SiO2)
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Banded Chert (Jasper)
Silicon Dioxide (SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide with Iron inclusions (SiO2)
Red Jasper
Jasper (Silicon Dioxide with Hematite inclusions), SiO2
Jasper
Silicon dioxide (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Jasper (Red Jasper)
Silicon Dioxide (SiO₂)
Jasper (Iron-rich)
Silicon Dioxide (SiO2) with Fe2O3 (Hematite) impurities
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Quartz (Milky Variant)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Jasper Breccia
Silicon Dioxide (SiO2) with impurities