Limonite (Iron Ore/Sandstone mixture)
Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix
Category
Browse organic (mineraloid) specimens identified by the Rock Identifier community.
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)
Snowflake Obsidian
Obsidian with Spherulitic Cristobalite (SiO2)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Obsidian
Volcanic Glass (predominantly SiO2, approximately 70% or more)
Mahogany Obsidian
Volcanic glass containing Magnetite/Hematite
Mahogany Obsidian
Obsidian (SiO2 + Fe2O3)
Limonite (Iron Ore)
Hydrous ferric oxides (FeO(OH)·nH2O)
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
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)
Baltic Amber (Butterscotch variety)
Succinite
Baltic Amber (Butterscotch or Egg Yolk Variety)
Succinite (C10H16O)
Obsidian
Obsidian (Volcanic Glass)
Snowflake Obsidian
Volcanic Glass with Spherulite inclusions (Chemical composition: 70–75% SiO2 + MgO, Fe3O4)
Obsidian (Black Obsidian)
Obsidian (Volcanic Glass)
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)
Obsidian
Obsidian (Extrusive Volcanic Glass)
Obsidian
Volcanic Glass (comprised primarily of SiO2)
Opalite
Synthetic Glass (Hydrated Crystalline Silicon Dioxide simulation)
Mahogany Obsidian
Volcanic glass (SiO2 + Fe2O3)
Black Obsidian
Volcanic Glass (predominantly SiO2, Silicon Dioxide)
Snowflake Obsidian
Volcanic Glass (spherulitic Obsidian) - SiO2 (with Cristobalite inclusions)
Limonite (Yellow Ochre)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
Limonite with Quartz (Gossan)
Hydrated iron(III) oxide-hydroxide mixture (FeO(OH)·nH2O) with Silicon Dioxide (SiO2)
White Opal (Common)
Hydrated Silica (SiO2·nH2O)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Limonite and Goethite (Ironstone)
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Obsidian
Obsidian (principally SiO2 with MgO and Fe3O4)
Tektite (likely Australite)
Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)
Limonite (Iron Ore)
Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)
Amber
Succinicum (C10H16O)
Amber and Citrine Quartz
Succinite (Amber) and Silicon Dioxide (SiO2 / Citrine)
Amber
Succinite (fossilized resin, C10H16O)
Naga Silver-Inlaid Ebony and Bone/Horn Beads
Diospyros (Ebony) or Keratin (Horn) with Silver/White-Metal Inlay