Ruby
Corundum (Aluminium Oxide with Chromium impurities, Al2O3:Cr)
Category
Browse mineraloid (synthetic) specimens identified by the Rock Identifier community.
Ruby
Corundum (Aluminium Oxide with Chromium impurities, Al2O3:Cr)
Pearl (Biogenic Mineral)
Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3
Snowflake Obsidian
Spherulitic Volcanic Glass (SiO2 + impurities)
Limonite Concretion
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Obsidian
Volcanic Glass (predominantly SiO2)
Chipped Glass/Plastic Fragment
Silicon dioxide (SiO2) for glass (amorphous) or various polymer compounds for plastic
Rose Quartz
Silicon Dioxide (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
Hematite
Iron(III) oxide (Fe2O3)
Obsidian
Volcanic Glass (Silicon Dioxide with impurities)
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)
Obsidian
Obsidian (Amorphous volcanic glass, SiO2 with impurities)
Snowflake Obsidian
Volcanic glass containing Spherulites (SiO2)
Amber
Succinite (with a generalized formula of C10H16O)
Blue Goldstone
Auraventurine (Synthetic glass with cobalt and copper inclusions)
Goldstone (with Tiger's Eye and Quartz)
Aventurine glass (Synthetic SiO2 with Cu inclusions)
Blue Goldstone
Aventurine Glass (SiO2 with Co and metallic inclusions)
Limonite (Iron Ore/Sandstone mixture)
Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix
Yellow Ocher (Limonite)
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
Obsidian
Volcanic Glass (Amorphous Silica)
Jadeite and Mixed Gemstones (Ruby, Sapphire, Emerald)
Jadeite (NaAlSi2O6), Corundum (Al2O3), Beryl (Be3Al2(Si6O18))
Staurolite (Cross Stone)
Staurolite (Fe2+2Al9Si4O23(OH))
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
SiO2 (Silicon Dioxide)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Ruby
Corundum (Al2O3) with Chromium traces
Hematite
Iron(III) oxide (Fe2O3)
Goldstone
Avventurina (Cu + SiO2 glass)
Smoky Quartz
Silicon Dioxide (SiO2)
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Common Opal with Host Rock
Opal (Hydrated silica, SiO2·nH2O)
Mahogany Obsidian
Obsidian (volcanic glass with hematite/magnetite inclusions)
Precious Opal
Hydrated Silica (SiO2·nH2O)
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Lapis Lazuli
Lazurite-dominant rock, (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2
Blue Goldstone
Aventurine Glass
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
Limonite (Yellow Ochre)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
Ring with an Orange Inlay
N/A (Man-made object)
Diamond
Native Carbon (C)
Obsidian
Obsidian (Volcanic Glass)
Snowflake Obsidian
Volcanic Glass with Spherulite inclusions (Chemical composition: 70–75% SiO2 + MgO, Fe3O4)