Sea Glass (Uranium/Vaseline Glass variant)
Silicon Dioxide (SiO2) with trace Uranium Oxide (U3O8)
man-made silicate (anthropogenic glass)
Category
Mineraloid (Man Made Glass)
Browse mineraloid (man made glass) specimens identified by the Rock Identifier community.
Granite
Phaneritic Felsic Igneous Rock
igneous
Titanium Aura Quartz (Aura Quartz)
Titanium-coated Silicon Dioxide (SiO2)
mineral
Anthracite Coal
Anthracite (Carbon-rich mineraloid)
metamorphic
Amber
Succinite (Organic Mineraloid) - C10H16O
mineral
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Pink Granite
Phaneritic Felsic Igneous Rock (composed of orthoclase, quartz, and plagioclase)
igneous
Goldstone (Red)
Aventurine Glass
Man-made material (Simulated Mineral)
Green Opal
Hydrated Silica (SiO2·nH2O)
mineraloid
Jasper Marble
Silicon Dioxide (SiO2) with Impurities
sedimentary
Sea Glass (Kelly Green)
Amorphous Silica (Silicon Dioxide with Iron/Chromium additives)
Anthropogenic specimen (Man-made material)
Sandstone
Arenite (primarily SiO2)
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Corundum (Sapphire variant)
Aluminium oxide (Al2O3)
mineral
Cardstock (Paper)
Cellulose (C6H10O5)n
sedimentary (man-made)
Opal
Hydrated Silica (SiO2·nH2O)
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)
mineral
Chert (often called Flint)
Chert (Cryptocrystalline Quartz, SiO2)
sedimentary
Amethyst
Amethyst (Silicon Dioxide - SiO2 with Iron impurities)
mineral
Chert (Flinty variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone (likely Quartzose)
Clastic sedimentary rock (SiO2 primary)
sedimentary
Limonite (Iron Ore)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
mineral
Jet
Lignite (Anthracite-grade compact coal)
sedimentary
Tektite (Indochinite)
Tektite (Amorphous Silica Glass)
igneous
Slag (Industrial Glass Slag)
Amorphous Silica / Ferro-silicate Slag
mineraloid / anthropogenic
Banded Chert (River Stone)
Silicon Dioxide (SiO2)
sedimentary
Sandstone (Quartz Arenite)
Sandstone (dominated by SiO2 quartz grains)
sedimentary
Cullet Glass (Industrial Slag Glass)
Amorphous Silica (SiO2) with metallic oxide impurities
Man-made byproduct (often mistaken for Obsidian or Emerald)
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Natural or Cultured Pearl
Calcium Carbonate (Aragonite and Conchiolin), CaCO3
Mineral (Organic)
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Amber
Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mineral
Quartzite (River Pebble)
Quartzite (Mainly SiO2)
metamorphic
Limonite (Iron Stone/Ocher)
Limonite (FeO(OH)·nH2O)
mineral
Limonite/Goethite on Shale
Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock
sedimentary
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
sedimentary
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Slag (Industrial Byproduct)
Ferro-silicate glass (Slag)
Anthropogenic (Man-made industrial deposit)
Mahogany Obsidian Arrowhead
Volcanic Glass with Hematite/Magnetite inclusions (Amorphous Silicon Dioxide)
igneous