Petrified Wood
Silicified Wood (primarily Silicon Dioxide, SiO2)
Category
Browse organic gemstone (not a mineral) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (primarily Silicon Dioxide, SiO2)
Quartz (Milky/Rose variety)
Silicon Dioxide (SiO2)
Amber (Rough)
Amber (Fossilized Tree Resin, succinite)
Chert (and Chert-based Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
Citrine
SiO2 (Silicon Dioxide)
Petrified Wood
Silicified Wood (SiO2)
Pyrite
Iron Sulfide (FeS2)
Petrified Wood
Silicified wood (Quartz, Chalcedony, or Opal)
Chert (Chalcedony)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
Druzy Chalcedony/Quartz on Fluorite core
Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)
Amber
Succinite
Pyrite Geode
Iron Disulfide (FeS2)
Chert (Brown Variety)
Silicon dioxide (SiO2)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
Chert (Chalky/Gray Variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Fossilized Crab Carapace (Concretion)
Decapoda (fossil), typically preserved in calcite or siderite concretion
Moqui Marbles
Iron Oxide Concretion (Hematite/Goethite)
Petrified Wood
Silicified wood (primarily SiO2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (varietal Flint or Jasper)
Microcrystalline Quartz (SiO2)
Cubic Zirconia (Faceted)
Zirconium dioxide (ZrO2)
Chert (specifically Red Chert/Jasper variety)
Silicon Dioxide (SiO2)
Tufa (Limestone)
Calcareous Tufa (CaCO3)
Fossilized Fish Skeleton in Matrix
Vertebrata (Class: Actinopterygii), typically found in limestone or shale matrices
Petrified Dinosaur Bone (Gembone)
Agatized Dinosaur Bone
Jasper
Silicon dioxide (SiO2)
Green Sandstone
Glauconitic Sandstone
Chert (often called Jasper in this color variety)
Microcrystalline Quartz (SiO2)
Chert (Flint/Chalcedony)
Microcrystalline Quartz (SiO2)
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
Petrified Wood
Silicified wood (Quartz, SiO2)
Chert (specifically Tan/Yellow Chert)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Baroque Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin)
Chert with Quartz/Calcite Vein
Microcrystalline Silica (SiO2)
Dendritic Agate / Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions
Amber
Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)