Petrified Wood
Silicified wood (principally SiO2)
Category
Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified wood (principally SiO2)
Malachite with Chrysocolla
Copper carbonate hydroxide (Cu2CO3(OH)2) and Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Chert (specifically Flint)
Microcrystalline Quartz (SiO2)
Chert (and its variety Flint)
Silicon dioxide (SiO2) / Microcrystalline quartz
Jasper (Iron-stained Quartzite/Chert)
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) impurities
Jasper
Jasper / Silicon Dioxide (SiO₂)
Yellow Jasper / Chert
Jasper (Silica/Quartz) - SiO2
Milky Quartz
Silicon Dioxide (SiO2)
Yellow Calcite
Calcite (Calcium Carbonate, CaCO3)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Red Jasper (Chert)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
Amber
Succinite (Resinous fossilized tree sap)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Chert (Nodule)
Chert (composition: SiO2)
Chert (Light Grey / Flint variant)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (specifically Red Chert / Jasper)
Silicon Dioxide (SiO2)
Chert (Yellow/Tan)
Microcrystalline Quartz (SiO2)
Chert Nodule (Fossiliferous Chert)
Microcrystalline Quartz (SiO2)
Quartz (specifically Milky/White Quartz)
Silicon Dioxide (SiO2)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)
Chert (specifically Tan Chert or Flint)
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide with Iron Oxide impurities (SiO2 + Fe2O3)
Rhodonite
Manganese silicate (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Red Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
Chert (Jasper)
Silicon dioxide (SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Black Pearl (Tahitian Pearl)
Aragonite / Calcite (CaCO3) with Conchiolin
Rhodonite
Rhodonite (Manganese Iron Magnesium Calcium Silicate - (Mn,Fe,Mg,Ca)SiO3)
Banded Chert
Microcrystalline Quartz (SiO2)
Chert (Black Chert or Flint)
Silicon Dioxide (SiO2)
Amazonite
Microcline (KAlSi3O8) with lead impurities
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Chert (specifically Flint or Jasper variant)
Silicon Dioxide (SiO2)
Pyrite
Pyrite (FeS2)
Green Chert
Microcrystalline Quartz (SiO2)
Chert (Iron-stained or Dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Shale
Shale
Chert (often called Jasper in this color)
Microcrystalline quartz (SiO2)