Tumbled mahogany obsidian
Volcanic glass; primarily SiO₂ with iron-oxide-rich brown inclusions
Category
Browse mineraloid (man made glass) specimens identified by the Rock Identifier community.
Tumbled mahogany obsidian
Volcanic glass; primarily SiO₂ with iron-oxide-rich brown inclusions
Obsidian (volcanic glass), likely black obsidian
Rhyolitic volcanic glass; predominantly amorphous SiO₂
Tumbled black stone, likely black obsidian
Obsidian — natural volcanic glass, primarily SiO₂
Obsidian
Volcanic Glass (Amorphous Silica)
Jewelry Chain with Blue and Clear Gemstones (Likely Cubic Zirconia)
Cubic Zirconia (ZrO₂), Silver or White Gold/Platinum Alloy
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with inclusions of Hematite or Magnetite)
Slag (Anthropogenic Glass/Iron byproduct)
Ferro-silicate Slag
Blue Slag Glass
Amorphous Silica (Byproduct of smelting)
Porcelain (Stoneware Ceramic)
Mullite / Silica-glass composite (Al6Si2O13)
Obsidian
Volcanic glass
Polished black obsidian
Volcanic glass; primarily silica-rich rhyolitic composition (approximately 70–80% SiO₂)
Anthracite Coal
Anthracite (Carbon-rich mineraloid)
Amber
Succinite (Organic Mineraloid) - C10H16O
Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
Obsidian
Volcanic Glass (felsic composition)
Mahogany Obsidian
Volcanic glass containing Magnetite/Hematite
Green Aventurine
Quartz (SiO2) with Fuchsite inclusions
Obsidian
Obsidian (Volcanic Glass)
Obsidian (Black Obsidian)
Obsidian (Volcanic Glass)
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Limonite or Ironstone Nodule
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)
Black obsidian
Volcanic glass; predominantly rhyolitic silica-rich melt (approximately 70–80% SiO₂), lacking crystalline structure
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Snowflake Obsidian
Volcanic Glass with Spherulite inclusions (Chemical composition: 70–75% SiO2 + MgO, Fe3O4)
Corundum (Pink Sapphire / Ruby)
Al2O3 (Aluminum Oxide)
Man-made Green Quartz (Lab-grown or Treated)
Silicon Dioxide (SiO2) with artificial coloration
Orange glassy slag (industrial by-product)
Iron-rich silicate glass; composition varies, commonly Fe–Ca–Al silicate
Amber
Succinite (with a generalized formula of C10H16O)
Obsidian
Volcanic Glass (Amorphous SiO2)
Likely obsidian fragment
Volcanic glass, predominantly silica-rich rhyolitic composition (SiO₂-rich)
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
Rough Diamond
Native Carbon (C)
Red cabochon gemstone ring (likely glass or synthetic stone)
Undetermined; the image does not establish a natural mineral identity
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)
Obsidian
Volcanic glass (Amorphous silicon dioxide)
Polished mahogany obsidian
Volcanic glass; primarily silica-rich rhyolitic composition (approximately 70–75% SiO₂)
Obsidian (likely black obsidian)
Volcanic glass, predominantly rhyolitic to dacitic silica-rich melt; approximate composition ~70–75% SiO₂
Metal Chain (Likely Steel or a Steel Alloy)
Steel (primarily iron and carbon); specific alloy unknown
Likely obsidian (rough fragment)
Volcanic glass, predominantly silica-rich rhyolitic composition (SiO₂-rich, noncrystalline)
Sea Glass
Amorphous silicon dioxide (glass)