Chalcedony (Botryoidal)
Silicon Dioxide (SiO2)
Category
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Chalcedony (Botryoidal)
Silicon Dioxide (SiO2)
Quartz (likely Rose Quartz or Milky Quartz based on color)
Quartz (SiO2 - Silicon Dioxide)
Yellow Quartzite
Quartzite (SiO2 with iron oxide inclusions)
Tiger's Eye
Silicon dioxide with crocidolite fibers (SiO2 with chrysotile amphibole inclusions)
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Schist (Garnet-Mica Schist)
Garnet-Mica Schist (X-Y)3Z2(SiO4)3
Aventurine (likely Green Aventurine)
Silicon Dioxide (SiO2) with mineral inclusions
Shungite
Non-crystalline carbon (allotrope of carbon)
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Smoky Quartz
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Chert (Silicon Dioxide, SiO2)
Amethyst (Tumbled)
Silicon Dioxide (SiO2) with iron impurities
Clear/White Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Chert (specifically Jasper or Flint type)
Microcrystalline Quartz (SiO2)
Chalcedony (Common Opal variant)
Silicon dioxide (SiO2) with varying levels of hydration
Jasper Agate
Silicon dioxide (SiO2)
Lazulite
Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2
Dendritic Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Unakite
Unakite (Epidotized Granite)
Unakite
Epidotized Granite
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Amber
Amber (Amorphous Organic Hydrocarbon)
Nuummite
Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions
Chert (Black Flint)
Silicon Dioxide (SiO2)
Mother of Pearl and Onyx
Aragonite (Mother of Pearl) and Chalcedony (Onyx)
Synthetic Resin Charm (Seal Shape)
Polymer Resin with plastic glitter / Polyethylene terephthalate glitters
Bouncy Ball (Synthetic Rubber Polymer)
Polybutadiene / Ethylene Vinyl Acetate (EVA)
Chert Pebble
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Green Jasper (with Quartz veining)
Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2
Dalmatian Jasper (Dalmatian Stone)
Perthitic feldspar with Arfvedsonite inclusions
Green Moss Agate / Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz with Iron and Manganese inclusions
Moss Agate
Silicon Dioxide with inclusions (SiO2)
Unakite
Unakite (Epidotized Granite)
Banded Chert (Ironstone/Jasper)
Cryptocrystalline Quartz (SiO2) with Iron Oxides
Amethyst
SiO2 (Silicon Dioxide)
Lapis Lazuli
Lapis lazuli (complex rock composed of Lazurite, Calcite, and Pyrite)
Amber (with potentially inclusions)
Succinite (Fossilized Tree Resin)
Coral (Precious Coral)
Corallium rubrum (Red Coral), Paracorallium japonicum (Momo Coral), Pleurocorallium elatius (Sardinian Coral), various other species within the Corallidae family. Chemically, it's primarily Calcium Carbonate (CaCO 3 ).