Obsidian Arrowhead
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
igneous
Category
Amorphous Solid
Browse amorphous solid specimens identified by the Rock Identifier community.
Learn about Amorphous Solid in the encyclopedia
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Chrysocolla on Quartz
Chrysocolla (Cu2−xAlx(H2−xSi2O5)(OH)4·nH2O) often associated with Quartz (SiO2)
mineral
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
igneous
Aluminum Slag
Anthropogenic Aluminum (Al)
mineral
Apache Tear
Hydrated Obsidians (Volcanic Glass)
igneous
Baltic Amber
Succinite (Polmerized conifer resin)
mineraloid
Chakra Stone Tower (Composite Multi-Mineral)
Crystalline Silicon Dioxide composite (SiO2) with various inclusions
mineral
Apache Tear (Obsidian)
Volcanic glass (SiO2 - Silicon Dioxide)
igneous
Amber
Fossilized tree resin (Amorphous organic polymer)
gemstone
Pumice
Vesicular Rhyolite or Andesite (Amorphous volcanic glass)
igneous
Green Obsidian Sphere (man-made glass)
Vitreous Silica with Chromium/Iron additives
mineralogical simulant
Coquina
Biogenic Limestone (Calcite/Aragonite, CaCO3)
sedimentary
Sandstone
Sandstone (arenite is a more specific geological term for a clean sandstone, while wacke refers to a dirty sandstone with significant matrix)
Sedimentary
Sandstone (with possibly iron oxides and other minerals)
Sandstone
Sedimentary rock
Man-made Carved Stone (Scream Mask/Skull motif)
Carved Soapstone or Serpentine-rich rock
Anthropogenic (Man-made artifact)
Blue Goldstone
Synthetic Aventurescent Glass (Cobalt-doped soda-lime glass)
man-made glass
Green Sea Glass
Amorphous Silica (man-made glass), SiO2 + additive metal oxides
mineraloid / anthropogenic (man-made origin)
Goldstone (aventurine glass)
Man-made copper-bearing glass; not a natural mineral (commonly sold as blue/brown goldstone)
mineral
Red Slag Glass (Cullet)
Amorphous Silicon Dioxide (SiO2) with metallic dopants
Antropogenic (Man-made material)
River Pebble
Weathered Rock Fragment
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Copper Ore (Malachite and Limonite bearing)
Cuprite, Malachite, and Limonite mixture
mineral
Chert
Microcrystalline quartz (SiO2)
sedimentary
Pumice
Pumice (Volcanic Rock / Glass Froth)
igneous
Fulgurite
Lechatelierite (Silica glass tubes)
mineral
Amber
Fossilized Tree Resin
gemstone
Flint / Chert with Fossils
Cryptocrystalline quartz (SiO2) with embedded fossil impressions
sedimentary
Limonite with Quartz
Hydrated Iron Oxide Hydroxide with Silicon Dioxide (FeO(OH)·nH2O + SiO2)
mineral
Sand Tiger Shark Tooth
Carcharias taurus
fossil
Pebbles
Polymictic rock fragments
sedimentary
Yellow Ochre
Goethite-rich clay (Hydrated Iron Oxide: FeO(OH)·nH₂O)
mineral
Coal (Bituminous / Anthracite)
Organic Sedimentary Rock (Carbonaceous Rock)
sedimentary
Amber
Succinite (Fossilized Tree Resin)
gemstone
Limonite (Ironstone)
Hydrated Iron(III) Oxide-hydroxide (FeO(OH)·nH2O)
sedimentary
Goldstone
Avventurina (Man-made Glass with Copper inclusions)
mineral
Pumice
Pumice (extrusive volcanic rock)
igneous
Snowflake Obsidian
Volcanic glass with Phenocrysts (SiO2)
igneous
Mahogany Obsidian
Volcanic Glass (SiO2 with Fe/Mg oxides)
igneous
Anthracite Coal
Anthracite
metamorphic
Apache Tears (Tumbled Obsidian)
Volcanic Glass (SiO2 + impurities)
igneous
Blue Goldstone
Aventurine Glass
man-made glass
Tektite (Indochinite)
Impactite / Tektite (Silica-rich glass)
igneous