Chert
Microcrystalline Quartz (SiO2)
sedimentary
Category
Man Made Material (Anthropogenic 'Mineraloid')
Browse man made material (anthropogenic 'mineraloid') specimens identified by the Rock Identifier community.
Learn about Man Made Material (Anthropogenic 'Mineraloid') in the encyclopedia
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Pearl
Pearl (Calcium Carbonate with organic conchiolin, CaCO3)
mineral
Diamond
Carbon (C)
gemstone
Banded agate pendant (likely carnelian or brown-and-white chalcedony agate)
Agate, a banded variety of chalcedony; microcrystalline quartz, SiO₂, with iron-oxide coloration
gemstone
Diamond
Carbon (C)
gemstone
Cardstock (Paper)
Cellulose (C6H10O5)n
sedimentary (man-made)
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (Calcium Carbonate, CaCO3)
Sedimentary
Goldstone
Avventurina (Cu + SiO2 glass)
mineral
Basalt
Basalt
igneous
Diamond
Carbon (C)
gemstone
Mother of Pearl (Nacre)
Calcium Carbonate (primarily aragonite, with conchiolin)
Organic Gemstone/Biomineral
Chert (Flint)
Chert (Microcrystalline or cryptocrystalline Quartz - SiO2)
sedimentary
Chert (specifically Zebra Chert/Flint)
Silicon Dioxide (SiO2)
sedimentary
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flinty variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Granite
Phaneritic plutonic rock (SiO2 typically >69%)
igneous
Note: Item is not a geological specimen
Polyester mesh and Ethylene-vinyl acetate (EVA) polymer
Synthetic / Anthropogenic Material
Flint
Silicon Dioxide (SiO2) - Chert variety
sedimentary
Blue Goldstone
Aventurine glass (Synthetic borosilicate glass with cobalt and metallic inclusions)
man-made glass
Porcelain (Stoneware Ceramic)
Mullite / Silica-glass composite (Al6Si2O13)
metamorphic (man-made)
Diamond
Carbon (C)
mineral
Coquina
Bioclastic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Megalodon Shark Tooth
Otodus megalodon
fossil
Pyrite
Iron Sulfide (FeS2)
mineral
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint)
Microcrystalline quartz (SiO2)
sedimentary
Tumbled iron-rich stone, likely hematite-bearing jasper
Jasper (microcrystalline quartz, SiO₂) with iron oxides, chiefly hematite/goethite
mineral
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
mineral
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Asphalt
Asphalt concrete (engineered material, not a naturally occurring rock/mineral in this form)
Sedimentary
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Chert (Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Slag (Industrial Glassy Byproduct)
Ferro-silicate Slag
Anthropogenic / Non-Natural
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Lapis lazuli and green-blue chalcedony jewelry
Lapis lazuli: lazurite-bearing metamorphic rock, chiefly lazurite (Na₃Ca(Al₃Si₃O₁₂)S) with calcite and pyrite; second stone: likely chrysoprase or green-blue chalcedony (microcrystalline quartz, SiO₂)
gemstone
Crushed Limestone
Calcium Carbonate (CaCO3)
Sedimentary
Granite
Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).
igneous
Coquina Limestone
Coquina (Biogenic Limestone)
sedimentary
Chert (Nodular or Massive Variety)
Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Iron-stained)
Chert (Microcrystalline and Cryptocrystalline Quartz, SiO2)
sedimentary
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
sedimentary
Tektite (Indochinite)
Tektite (High-silica natural glass)
mineraloid / impact glass