Pearl
Organic gemstone (Calcium carbonate - CaCO3)
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Pearl
Organic gemstone (Calcium carbonate - CaCO3)
Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Black Pearl (Tahitian Pearl)
Aragonite / Calcite (CaCO3) with Conchiolin
Chert (specifically Flint or Common Chert)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Amber
Succinite (C10H16O)
Chert (Jasper/Flint variant)
Microcrystalline quartz (SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Red Coral (with Hematite and Black Pearl accents)
Corallium rubrum (Calcium Carbonate, CaCO3)
Pearl (incorporated into jewelry)
Aragonite and Calcite (CaCO3)
Limestone (specifically Bituminous or Carbonaceous Limestone)
Calcium Carbonate (CaCO3) with Organic Impurities
Pearl
Calcium Carbonate (CaCO3) + Conchiolin
Pearl strand
Nacreous pearl, primarily aragonite (CaCO₃) with conchiolin protein
Chert (Nodular or Massive Variety)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Amber
Succinate (Fossilized Tree Resin)
Amber
Succinite (Approximate formula: C10H16O)
Chert (Gray Chalcedony)
Microcrystalline Quartz (SiO2)
Pink Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Amber
Succinit (C10H16O)
Carnelian (Orange Chalcedony)
Silicon Dioxide (SiO2)
Chert (specifically Jasper or Flint type)
Microcrystalline Quartz (SiO2)
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Field Flint)
Microcrystalline Quartz (SiO2)
Pearl
Calcium Carbonate (Aragonite/Calcite) with Conchiolin, CaCO3
Chert (Green variety)
Microcrystalline Opaline/Quartz (SiO2)
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
Chert / Flint
Silicon Dioxide (SiO₂)
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Possible weathered metallic meteorite fragment
Unclassified iron-rich meteorite; exact classification requires laboratory testing
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Precious Red Coral
Corallium rubrum / Corallium japonicum
Chert (Agatized/Chalcedony variety)
Microcrystalline Quartz (SiO2)
Baltic Amber (Butterscotch or Egg Yolk Variety)
Succinite (chemical formula: C10H16O)
Amber
Succinite (Fossilized Tree Resin)
Amber
Succinite (fossilized resin)
Amber
Fossilized Tree Resin
Fossiliferous Sandstone
Sedimentary rock containing invertebrate fossils