Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained River Cobble)
Microcrystalline Quartz (SiO2)
Turquoise
CuAl6(PO4)4(OH)8·4H2O
Red Jasper
Jasper (Silicon Dioxide with Hematite inclusions), SiO2
Chalcedony (Botryoidal/Tumbled Agate)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
Jasper
Silicon dioxide (SiO2) with iron inclusions
Red Jasper
Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Carnelian and White Quartz Bracelet
Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz
Petrified Wood
Silicified Wood (SiO2)
Dalmation Stone
Peralkaline Rock (mixed silicate minerals)
Quartz (Milky/Rose variety)
Silicon Dioxide (SiO2)
Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Rhodochrosite
Manganese carbonate (MnCO3)
Pink Garnet (likely Almandine or Rhodolite)
Garnet Group (Fe3Al2(SiO4)3 to Mg3Al2(SiO4)3)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Yellow Jasper
Jasper (SiO2) with iron hydroxide inclusions
Jasper (Iron-rich)
Silicon Dioxide (SiO2) with Fe2O3 (Hematite) impurities
Dendritic Agate (or Dendritic Opal)
SiO2 (for Agate), SiO2·nH2O (for Opal)
Precious Opal
Hydrated Silica (SiO2·nH2O)
Rhodochrosite
Manganese carbonate (MnCO3)
Jasper Breccia
Silicon Dioxide (SiO2) with impurities
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Travertine (Tufa)
Calcium Carbonate (CaCO3)
Red Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
Orange Calcite (Mexican Onyx)
Calcium Carbonate (CaCO3)
Shale
Shale (clastic sedimentary rock)
Turquoise in Matrix
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Quartz (Milky Variant)
Silicon Dioxide (SiO2)
Turquoise (Rough)
Hydrated phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Milky Quartz
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (primarily SiO2)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
Red Jasper (Quartz)
Silicon Dioxide (SiO2) with Iron impurities
Blue Apatite
Fluoroapatite (Ca5(PO4)3F)
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Quartzite and Chert
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions