Obsidian
Volcanic Glass (predominantly SiO2)
Category
Browse mineral (specifically a mineraloid) specimens identified by the Rock Identifier community.
Obsidian
Volcanic Glass (predominantly SiO2)
Bumblebee Jasper
Calcite with Arsenic and Sulfur inclusions
Yellow Ocher (Limonite)
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
Precious Coral (Red Coral)
Corallium rubrum (Calcium Carbonate, CaCO3)
Moonstone (Green Moonstone / Garnierite)
Potassium Aluminum Silicate (KAlSi3O8) with inclusions of Garnierite
Limonite (Iron Ore)
Hydrous ferric oxides (FeO(OH)·nH2O)
Tektite (specifically Indochinite)
Tektite (Natural silica glass)
Amber
Succinite (Organic Mineraloid) - C10H16O
Opal
Hydrated silica (SiO2 "NH2O)
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)
Amber (Copal)
Fossilized Tree Resin
Opal
Hydrated silica (SiO2·nH2O)
N/A - Image does not contain a rock or mineral
Anthropogenic textile material
Opal
Hydrated amorphous silica (SiO2·nH2O)
Pink Satin Spar (Satin Spar Selenite Dyed)
Gypsum (CaSO4·2H2O)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Tumbled black stone, likely black obsidian
Obsidian — natural volcanic glass, primarily SiO₂
Obsidian
Volcanic Glass (SiO2)
Obsidian
Volcanic Glass (predominantly SiO2, approximately 70% or more)
Limonite/Ironstone
Limonite (FeO(OH)·nH2O)
Limonite with Quartz (Gossan)
Hydrated iron(III) oxide-hydroxide mixture (FeO(OH)·nH2O) with Silicon Dioxide (SiO2)
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Obsidian
Volcanic Glass (Amorphous Silica)
Thunderegg (specifically a Jasper/Agate-filled Geode nodule)
Silicon Dioxide (SiO2) within Rhyolitic Matrix
Amber
Succinite (Fossilized Tree Resin)
Amber (Raw)
Succinite (Fossilized Resin)
Amber
Succinite (with a generalized formula of C10H16O)
Amber
Succinates
Fuchsite
K(Al,Cr)2(AlSi3)O10(OH)2
Amber
Succinite (approximate formula C10H16O)
Amber
Succinite (C10H16O)
Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
Abalone Shell (Nacre)
Aragonite (CaCO3) - Biogenic Mineral
Pearls
Aragonite (calcium carbonate) and Conchiolin
Black Obsidian
Obsidian (Volcanic Glass)
Snowflake Obsidian
Volcanic Glass with Spherulite Inclusions (70–75% SiO2)
Mahogany Obsidian
Volcanic glass (SiO2 with Hematite or Magnetite inclusions)
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite inclusions
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
Amber
Succinates (Fossilized Tree Resin)
Amber
Amber (Succinite), fossilized tree resin
Amber (with potentially inclusions)
Succinite (Fossilized Tree Resin)