Emerald
Beryl (Be3Al2(SiO3)6) colored by Chromium and/or Vanadium
Category
Browse mineraloid (synthetic) specimens identified by the Rock Identifier community.
Emerald
Beryl (Be3Al2(SiO3)6) colored by Chromium and/or Vanadium
Mahogany Obsidian
Volcanic Glass with Hematite inclusions
Black Obsidian
Volcanic Glass (SiO2 + MgO / Fe3O4)
Black Obsidian
Volcanic Glass (SiO2)
Snowflake Obsidian
Volcanic glass (SiO2) with Cristobalite (SiO2) inclusions
Snowflake Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with Cristobalite inclusions)
Obsidian
Obsidian (volcanic glass; primarily SiO2)
Mahogany Obsidian
Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2
Obsidian
Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
Obsidian
Volcanic glass (high silica volcanic rock)
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2 with Cristobalite inclusions)
Black Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2
Limonite (Iron Ore Congcretion)
Limonite (a mixture of hydrated iron(III) oxide-hydroxides, FeO(OH)·nH2O)
Shungite
Carbon-rich mineraloid (Amorphous carbon)
Coal (Bituminous or Anthracite)
Carbonaceous Sedimentary Rock
Ruby (varietal of Corundum)
Corundum (Al2O3:Cr)
Milky Quartz
Crystalline Silicon Dioxide (SiO2)
Spinel
Magnesium Aluminum Oxide (MgAl2O4)
Ruby
Corundum (Al2O3 with Chromium trace)
Rough Ruby
Corundum (Al2O3 with Chromium impurities)
Smoky Quartz
Silicon Dioxide (SiO2)
Blue Sapphire
Corundum (Al2O3 with Cr, Fe, and Ti trace elements)
Tumbled mahogany obsidian
Volcanic glass; primarily SiO₂ with iron-oxide-rich brown inclusions
Black Obsidian
Amorphous volcanic glass (SiO2)
Obsidian (specifically Mahogany Obsidian)
Volcanic glass (high silica content, SiO2)
Obsidian with Mahogany Phasing
Volcanic Glass (SiO2 + Fe2O3)
Obsidian
Obsidian (Volcanic Glass; SiO2 content > 70%)
Mahogany Obsidian
Volcanic Glass (SiO2 + Fe2O3)
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Limonite (Iron Stone/Goethite)
Limonite (mixture of hydrated iron oxides, primarily Goethite: α-FeO(OH))
Pearl (Biogenic Mineraloid)
Calcium carbonate (CaCO3) primarily as Aragonite
Blue Sapphire (in a faceted jewelry setting)
Corundum (Al2O3) with trace Iron and Titanium
Ruby
Corundum (Al2O3)
Ruby
Corundum (Al2O3 with Chromium)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
Fire Opal (in Matrix)
Hydrated Silica (SiO2·nH2O)
Cherry Quartz with Rose Quartz
Crystalline Quartz (SiO2) with glass-based synthetic components
Carborundum (Silicon Carbide)
Silicon Carbide (SiC)
Cubic Zirconia (Faceted)
Zirconium dioxide (ZrO2)