Opalite
Synthetic Fluorescent Glass (SiO2 + impurities)
mineraloid (synthetic)
Category
Organic Crystal (Mineraloid)
Browse organic crystal (mineraloid) specimens identified by the Rock Identifier community.
Opalite
Synthetic Opalised Glass
mineraloid (synthetic)
Amber
Succinite (fossilized resin)
mineral
Slag (Industrial Glass Slag)
Amorphous Silica / Ferro-silicate Slag
mineraloid / anthropogenic
Red Coral
Corallium rubrum
mineral
Jade
Jadeite or Nephrite
Mineral/Mineraloid
Red Coral (with Hematite and Black Pearl accents)
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Jade (likely Jadeite or Nephrite)
Jadeite (NaAlSi2O6) or Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)
Mineral/Mineraloid
Obsidian
Obsidian (volcanic glass)
Igneous
Jasper containing fossilized inclusions
Silicon Dioxide (SiO2) with trace impurities and biogenic inclusions
sedimentary
Pyritized Ammonite
Ammonitida (replaced by Iron Disulfide, FeS2)
sedimentary
Aragonite (Star Cluster or Twinned variety)
Aragonite (Calcium Carbonate, CaCO3)
mineral
Opalite
Man-made Glass (SiO2 + additives)
mineraloid (synthetic)
Smurf Rock (Fictional Interpretation)
Cyanus Anthropomorphicus (Geologic Simulation)
Artificial/Fantasy Object
Amber
Succinite (fossilized resin, C10H16O)
mineral
Amber
Succinite
mineral
Freshwater Pearl
Aragonite / Biogenic Calcium Carbonate (CaCO3)
mineral
Human Skin (Epidermis/Dermis)
Integumentary tissue (High content of hydroxyapatite in bones, though the surface is biological)
Mineral-like biological tissue
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
sedimentary
Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite
mineral
Chert (specifically Gray/Black Chert)
Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcendony replacing organic matter)
sedimentary
Amber
Succinite (C10H16O)
mineral
Pearl
Calcium carbonate (CaCO3) in the form of Aragonite or Calcite
mineral
Pearl
Calcium carbonate (CaCO3) as Aragonite or Calcite
mineral
Orthoceras Fossil Limestone
Orthoceras (extinct Cephalopod fossil) in Matrix
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Coquina / Shelly Limestone
Coquina (Biogenic Limestone)
sedimentary
Amber Inlay Jewelry
Fossilized Resin (C10H16O)
Organic Gemstone (Biogenic)
Paper (Cellulose)
Cellulose (C6H10O5)n
Organic (Anthropogenic)
Chrysanthemum Stone
Celestine (SrSO4) or Calcite (CaCO3) in Limestone/Porphyry matrix
metamorphic
Bituminous Coal
Organic Sedimentary Rock (Carbon-based)
sedimentary
Amber
Organic gemstone (Succinite)
mineral
Kidney Stone
Calcium Oxalate (CaC2O4), Uric Acid, or Struvite
mineral
Sandstone (Weathered Coastal Boulder)
Arenite (composed primarily of SiO2)
sedimentary
Chert (often called Flint)
Chert (Microcrystalline Silicon Dioxide, SiO2)
sedimentary
Amber / Copal
Organic resin, C10H16O
mineral
Herkimer Diamond
Quartz (Silica - SiO2)
mineral
Amber
Succinite (Organic Gemstone)
mineral
Shungite
Non-crystalline carbon (allotrope of carbon)
metamorphic
Anthracite Coal
Anthracite (Carbon-based metamorphic rock, 86-97% C)
metamorphic
Stromatolite (Fossiliferous Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary