White Precious Opal
Hydrated Silica (SiO2·nH2O)
Category
Browse organic mineraloid and mineral specimens identified by the Rock Identifier community.
White Precious Opal
Hydrated Silica (SiO2·nH2O)
Obsidian
Volcanic Glass (comprised primarily of SiO2)
Black Obsidian
Volcanic Glass (predominantly SiO2, Silicon Dioxide)
Mahogany Obsidian
Obsidian (SiO2 + Fe2O3)
Limonite (Iron Ore)
Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)
Snowflake Obsidian
Volcanic glass containing Spherulitic Cristobalite (SiO2)
Snowflake Obsidian
Volcanic Glass (spherulitic Obsidian) - SiO2 (with Cristobalite inclusions)
Limonite and Goethite (Ironstone)
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
Cullet Glass (Man-made Glass Slag)
Amorphous Silica (SiO2) with chemical additives
Opal (Precious Opal)
Hydrated Silica (SiO2·nH2O)
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Cullet Glass (Slag)
Amorphous Silicon Dioxide (Man-made)
Sea Glass (Frosted Quartz/Glass)
Amorphous Silicon Dioxide (SiO2)
Fire Opal (in Matrix)
Hydrated Silica (SiO2·nH2O)
Amber
Succinicum (C10H16O)
Obsidian
Obsidian (principally SiO2 with MgO and Fe3O4)
Snowflake Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with Cristobalite inclusions)
Mahogany Obsidian
Volcanic glass (SiO2 + Fe2O3)
Cullet Glass (Slag Glass)
Amorphous Silicon Dioxide (Industrial byproduct)
Amber and Citrine Quartz
Succinite (Amber) and Silicon Dioxide (SiO2 / Citrine)
Amber
Succinite (fossilized resin, C10H16O)
Amber
Resinite / Fossilized Tree Resin
Kidney Stone
Nephrolithiasis (Calcium Oxalate, Hydroxyapatite, or Uric Acid)
Snowflake Obsidian
Obsidian with Spherulitic Cristobalite (SiO2)
Snowflake Obsidian
Volcanic glass containing Spherulites (SiO2)
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Precious Opal
Hydrated Silica (SiO2·nH2O)
Opalite
Synthetic Glass (Hydrated Crystalline Silicon Dioxide simulation)
Natural Pearl
Calcium carbonate (primarily Aragonite and Conchiolin), CaCO3
Amber
Succinite (C10H16O)
Jade (likely Jadeite or Nephrite)
Jadeite (NaAlSi2O6) or Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)
Baltic Amber (Butterscotch variety)
Succinite
Baltic Amber (Butterscotch or Egg Yolk Variety)
Succinite (C10H16O)
Fossil Shark Tooth
Carcharodon sp. (likely Otodus or similar Lamniformes order)
Pearl
Organic Mineral (CaCO3 with conchiolin)
Tektite (likely Australite)
Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)
Pearl
Calcium Carbonate (CaCO3) + Conchiolin
Amber
Succinite (specifically for Baltic Amber), Formula: C10H16O
Manganese-coated Sandstone
Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)
Amber
Fossilized Resin (C10H16O)
Jade
Jadeite or Nephrite