Limonite/Goethite on Shale
Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock
Category
Browse mineral (specifically a mineraloid) specimens identified by the Rock Identifier community.
Limonite/Goethite on Shale
Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock
Black Obsidian
Obsidian (Amorphous Silicon Dioxide)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)
Slag Glass (Cullet)
Amorphous Silica (man-made), primarily SiO2 with trace metal oxides
Limonite (Yellow Ochre)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Limonite (Iron Ore)
Limonite (Hydrated iron oxide - FeO(OH)·nH2O)
Limonite (Yellow Ochre)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Limonite (Ironstone)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Common Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mahogany Obsidian
Obsidian (volcanic glass with hematite/magnetite inclusions)
Black Obsidian
Obsidian (Volcanic Glass, SiO2+)
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2)
Black Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Limonite/Goethite Concretion
Hydrated Iron(III) Oxide-hydroxide (FeO(OH)·nH2O)
Obsidian
Obsidian (Volcanic Glass)
Amber with Organic Inclusions
Succinite (fossilized resin)
Amber
Succinite (organic mineraloid); Chemical formula: C10H16O
Tektite (specifically Indochinite)
Tektite (Natural silica glass)
Obsidian
Volcanic Glass (SiO2)
Limonite (Iron Ore)
Limonite (Hydrous ferric oxides), generic formula FeO(OH)·nH2O
Amber
Succinates
Limonite (Hydrated Iron Oxide / Bog Iron)
FeO(OH)·nH2O
Opal
Hydrated Silica (SiO2·nH2O)
Polished mahogany obsidian
Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)
Polished mahogany obsidian
Volcanic glass; predominantly silica-rich rhyolitic composition (SiO₂)
Polished black obsidian
Volcanic glass; predominantly rhyolitic silica glass (approximately 70–80% SiO₂)
Black Obsidian
Volcanic Glass (SiO2)
Black Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
Obsidian
Volcanic Glass (70-75% SiO2)
Mahogany Obsidian
Volcanic Glass with Hematite inclusions (SiO2 + Fe2O3)
Obsidian
Volcanic Glass (SiO2)
Amber
Succinite (specifically for Baltic amber); Complex mixture of organic compounds (C10H16O)
Glass
Amorphous Silicon Dioxide (SiO2)
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
Amber
Succinite
Common Opal (Green Opal / Pistachio Opal)
Hydrated silica (SiO2·nH2O)
Opal ring
Common opal, likely synthetic or assembled blue-green opal (hydrated amorphous silica, SiO₂·nH₂O)
Obsidian (likely black obsidian)
Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)
Obsidian (likely black obsidian)
Volcanic glass; primarily SiO₂-rich rhyolitic composition
Obsidian
Amorphous volcanic glass (SiO2)
Obsidian
Volcanic Glass (SiO2)
Obsidian
Obsidian (Volcanic Glass)