Mahogany Obsidian
Volcanic Glass (SiO2 with Fe/Mg oxides)
igneous
Category
Mineraloid
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Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
igneous
Common Opal (Potch)
Hydrated Silica (SiO2·nH2O)
mineral
Black Obsidian
Volcanic glass (Amorphous silicates)
igneous
Limonite with Quartz (Gossan)
Hydrated iron(III) oxide-hydroxide mixture (FeO(OH)·nH2O) with Silicon Dioxide (SiO2)
Mineral
White Opal (Common)
Hydrated Silica (SiO2·nH2O)
mineral
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
igneous
Obsidian
Obsidian (principally SiO2 with MgO and Fe3O4)
igneous
Cantera Opal (Mexican Fire Opal in Rhyolite Matrix)
Hydrated amorphous silica in rhyolite (SiO2·nH2O in volcanic matrix)
gemstone
Limonite and Goethite (Ironstone)
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
sedimentary
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)
Mineral (specifically a mineraloid)
Obsidian
Volcanic Glass (Amorphous silicon dioxide with trace impurities)
igneous
Limonite (Iron Ore)
Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)
Mineral
Amber
Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)
mineral
Amber-set ring
Amber (fossilized plant resin; organic mineraloid), set in a metal ring
gemstone
Red Sandstone
Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)
sedimentary
Amber (likely raw amber)
Fossilized tree resin; organic mineraloid, commonly containing succinite (not a true mineral)
gemstone
Mahogany Obsidian Arrowhead
Volcanic Glass with Hematite/Magnetite inclusions (Amorphous Silicon Dioxide)
igneous
Polished black stone, likely shungite
Shungite; carbon-rich mineraloid composed mainly of amorphous carbon, with silica and other minerals
mineral
Amber
Succinite (fossilized tree resin)
Organic Mineraloid
Amber
Succinate (Succinite for Baltic varieties)
Organic Mineraloid
Man-made Glass (Tumbled/Shaped)
Amorphous Silicon Dioxide (SiO2) with metal oxide colorants
Mineraloid (synthetic)
Opalite
Synthetic Fluorescent Glass (SiO2 + impurities)
mineraloid (synthetic)
Synthetic Convention Badge (Plastic/PVC)
Polyvinyl Chloride (PVC) / Polycarbonate
mineraloid (synthetic)
Amber
Succinite (C10H16O)
Mineraloid (Organic)
Jade (likely Jadeite or Nephrite)
Jadeite (NaAlSi2O6) or Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)
Mineral/Mineraloid
Jade
Jadeite or Nephrite
Mineral/Mineraloid
Amber
Succinite
Organic Mineraloid
Amber
Succinite (with formula approximately C10H16O)
Organic mineraloid
Pearl (Cultured or Natural)
Aragonite (CaCO3) with Conchiolin
Organic Mineraloid
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary (or mineraloid)
Amber
Succinite (Fossilized Tree Resin)
Organic Mineraloid
Opalite (Synthetic Moonstone/Opal)
Synthetic Silica Glass
mineraloid (synthetic)
Amber
Succinite (Fossilized Tree Resin), C10H16O
Organic Mineraloid
Opalite
Synthetic Opalised Glass
mineraloid (synthetic)
Cullet (Slag Glass)
Amorphous Silica (SiO2) with various metal oxide colorants
mineraloid / anthropogenic
Amber
Succinite (specifically for Baltic amber); Fossilized Tree Resin (C10H16O)
Organic Mineraloid
Amber
Succinite (specifically for Baltic amber); Complex mixture of organic compounds (C10H16O)
Organic Mineraloid
Pearl (nacre)
Calcium Carbonate (mostly CaCO3 as Aragonite) and Conchiolin
Organic Mineraloid
Amber
Succinite (a Fossilized Tree Resin); Chemical formula is approximately C10H16O
Organic mineraloid
Opalite
Synthetic Glass, SiO2 base with metallic inclusions
mineraloid (synthetic)
Amber
Succinite (formula varies, primarily C10H16O)
Mineraloid (Organic)