Carved quartz skull, likely smoky quartz or gray chalcedony
Silicon dioxide (SiO₂), quartz or microcrystalline quartz
Category
Browse man made material specimens identified by the Rock Identifier community.
Carved quartz skull, likely smoky quartz or gray chalcedony
Silicon dioxide (SiO₂), quartz or microcrystalline quartz
Jasper
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (and Flint)
Silicon Dioxide (SiO2)
Chert (specifically White Chert or Novaculite)
Silicon Dioxide (SiO₂)
Quartzite
Silica (SiO2) quartzite
Granite
Granite (Felsic Plutonic Rock)
Banded Sandstone
Arenite with Liesegang banding
Malaysian 50 Sen Coin
Coinage (specific alloy unknown without metallurgical analysis, but typically brass or bronze for this denomination and era)
Diorite
Intermediate plutonic igneous rock
Pearls (likely freshwater cultured pearls)
Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin
Bauxite
Bauxite (Al(OH)3, AlO(OH))
Coquina / Fossiliferous Limestone
Calcareous bioclastic sedimentary rock (CaCO3)
Diorite
Diorite
Diamond
Carbon (C)
Carved quartz (likely rose quartz and green aventurine/quartz)
Quartz, silicon dioxide (SiO₂); green material may be aventurine quartz or serpentine
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
Chert / Flint
Silicon Dioxide (SiO2)
Chert (Arrowhead Fragment)
Microcrystalline Quartz (SiO2)
Chert (specifically Black Chert or Flint)
Cryptocrystalline Quartz (SiO2)
Coquina
Biogenic Limestone (Calcite/Aragonite base, CaCO3)
Banded Calcite (often commercially sold as 'Mexican Onyx' or 'Honey Onyx')
Calcite (Calcium Carbonate, CaCO3)
Chert Arrowhead (Lithic Tool)
Microcrystalline quartz (SiO2) - Archeological lithic artifact
Granite
Granite (a plutonic rock)
Fossilized oyster shell
Bivalvia; likely an oyster (Ostreidae), partly mineralized with calcite
Marble
Recrystallized Calcite (CaCO3)
Diamond (Faceted)
Carbon (C)
Sandstone
Arenite (siliciclastic sedimentary rock composed mostly of quartz)
Sandstone (specifically Arkose or Quartz Arenite)
Arenite (primarily SiO2 with possible Feldspar)
Chert (specifically Jasper or Flint variety)
Cryptocrystalline Quartz (SiO2)
Granite
Phaneritic Igneous Rock (composed mostly of Quartz, Alkali Feldspar, and Plagioclase)
Chert
Microcrystalline Quartz (SiO2)
Pearl
Pearl (Calcium Carbonate with organic conchiolin, CaCO3)
Banded agate pendant (likely carnelian or brown-and-white chalcedony agate)
Agate, a banded variety of chalcedony; microcrystalline quartz, SiO₂, with iron-oxide coloration
Diamond
Carbon (C)
Diamond
Carbon (C)
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (Calcium Carbonate, CaCO3)
Diamond
Carbon (C)
Basalt
Basalt
Goldstone
Avventurina (Cu + SiO2 glass)
Blue Slag Glass
Amorphous Silica (Byproduct of smelting)
Cardstock (Paper)
Cellulose (C6H10O5)n