Obsidian
Obsidian (Volcanic Glass)
Category
Browse mineralogical specimens identified by the Rock Identifier community.
Obsidian
Obsidian (Volcanic Glass)
Limonite (Iron Stone/Ocher)
Limonite (FeO(OH)·nH2O)
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions (70–75% SiO2)
Obsidian
Amorphous volcanic glass (primarily SiO2)
Limonite/Goethite on Shale
Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock
Obsidian
Volcanic Glass (SiO2)
Amber
Succinite (Resinite)
Obsidian
Obsidian (Volcanic Glass)
Obsidian
Amorphous volcanic glass (SiO2)
Snowflake Obsidian
Volcanic Glass with Spherulite Inclusions (70-75% SiO2)
Amber with Organic Inclusions
Succinite (fossilized resin)
Limonite (Iron Ore)
Limonite (Hydrous ferric oxides), generic formula FeO(OH)·nH2O
Obsidian
Volcanic Glass (SiO2)
Amber
Succinates
Snowflake Obsidian
Volcanic glass containing Spherulitic Cristobalite (SiO2)
Obsidian
Volcanic Glass (70-75% SiO2)
Mahogany Obsidian
Volcanic Glass with Hematite inclusions (SiO2 + Fe2O3)
Opal
Hydrated Silica (SiO2·nH2O)
Gold Sheen Obsidian
Obsidian (volcanic glass with SiO2 + gas inclusions)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)
Obsidian
Volcanic Glass (SiO2)
White Precious Opal
Hydrated Silica (SiO2·nH2O)
Limonite (Hydrated Iron Oxide / Bog Iron)
FeO(OH)·nH2O
Black Obsidian
Amorphous volcanic glass (SiO2)
Mahogany Obsidian
Volcanic Glass (SiO2 + Fe2O3)
Obsidian (specifically Mahogany Obsidian)
Volcanic glass (high silica content, SiO2)
Obsidian
Obsidian (Volcanic Glass; SiO2 content > 70%)
Obsidian with Mahogany Phasing
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))
Black Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Snowflake Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with Cristobalite inclusions)
Snowflake Obsidian
Volcanic glass (SiO2) with Cristobalite (SiO2) inclusions
Mahogany Obsidian
Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2
Glass
Amorphous Silicon Dioxide (SiO2)
Obsidian
Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)
Obsidian
Volcanic glass (high silica volcanic rock)
Obsidian
Obsidian (volcanic glass; primarily SiO2)
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2 with Cristobalite inclusions)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2