Mahogany Obsidian
Volcanic glass containing Hematite or Magnetite (SiO2 + Fe2O3)
Category
Browse mineraloid (anthropogenic) specimens identified by the Rock Identifier community.
Mahogany Obsidian
Volcanic glass containing Hematite or Magnetite (SiO2 + Fe2O3)
Obsidian
Obsidian (Volcanic Glass)
Limonite (Iron Stone/Ocher)
Limonite (FeO(OH)·nH2O)
Obsidian
Amorphous volcanic glass (primarily SiO2)
Limonite/Goethite on Shale
Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions (70–75% SiO2)
Black Obsidian
Obsidian (Amorphous Silicon Dioxide)
Snowflake Obsidian
Volcanic Glass with Cristobalite Inclusions
Amber
Succinite (Resinite)
Amber with Organic Inclusions
Succinite (fossilized resin)
Obsidian
Obsidian (Volcanic Glass)
Mahogany Obsidian
Obsidian (volcanic glass with hematite/magnetite inclusions)
Black Obsidian
Obsidian (Volcanic Glass, SiO2+)
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2)
Limonite (Yellow Ochre)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Limonite (Yellow Ochre)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Black Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Obsidian
Obsidian (Volcanic Glass)
Limonite/Goethite Concretion
Hydrated Iron(III) Oxide-hydroxide (FeO(OH)·nH2O)
Limonite (Ironstone)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Limonite (Iron Ore)
Limonite (Hydrated iron oxide - FeO(OH)·nH2O)
Amber
Fossilized Tree Resin (Succinite)
Common Opal
SiO2·nH2O (Hydrated Silicon Dioxide)
Green Opal
Hydrated amorphous silica (SiO2·nH2O)
Amber (Copal)
Succiniferous Resin
Green Opal or Yellow Opal
Hydrated Silica (SiO2·nH2O)
Amber (Copal)
Fossilized Tree Resin
Amber
Succinate (Fossilized Tree Resin)
Green Opal
Hydrated amorphous silica (SiO2·nH2O) with inclusions
Amber (Copal)
Succinate (Fossilized Resin)
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
Opalite
Synthetic Glass (Amorphized Silicon Dioxide)
Common Opal (Green Opal / Pistachio Opal)
Hydrated silica (SiO2·nH2O)
Amber
Succinite (fossilized resin)
Amber
Succinite (Fossilized Tree Resin)
Amber
Succinite (fossilized tree resin)
Amber
Succinite (approximate formula C10H16O)
Amber
Succinrite (Organic Gemstone)
Amber
Succinite (a fossilized organic resin containing succinic acid)
Tektite (Indochinite)
Impact Glass (SiO2 + Al2O3)
Shungite
Carbonaceous rock (primarily amorphous carbon)