Chert (Yellow/Tan variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Category
Browse anthropogenic material (man made rock) specimens identified by the Rock Identifier community.
Chert (Yellow/Tan variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert Nodule (Flint)
Chert (Silicon Dioxide, SiO2)
Diamond
Diamond (Pure Carbon, C)
Granodiorite / Granite (Weathered)
Granodiorite
Blue Lace Agate
Chalcedony (SiO2) with trace inclusions
Chert (Siltstone / Flint)
SiO2 (Cryptocrystalline Quartz)
Sandstone
Arenite
Diamond (Cut jewelry specimen)
Diamond (pure Carbon, C)
Jasper
Silicon dioxide (SiO2) with impurities
Diamond
Diamond (pure Carbon, C)
Coquina
Bioclastic Limestone
Sandstone
Arenite (primarily SiO2)
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
Sandstone (Quartzose)
Arenite (composed primarily of SiO2)
Coquina
Biogenic Limestone (mostly Calcium Carbonate, CaCO3)
Chert (Common Opal/Jasper variety)
Cryptocrystalline Quartz (SiO2)
Diamond (in Jewelry)
Carbon (C)
Flint / Chert
Microcrystalline quartz (SiO2)
Chert (Black Chert or Flint)
Silicon Dioxide (SiO2)
Tektite (Indochinite)
Tektite (Amorphous Silica Glass)
Porcelain (Kaolin-based)
Alumina silicate ceramic (composed primarily of Kaolinite: Al2Si2O5(OH)4)
Polished blue stone, likely sodalite or dyed agate
Sodalite: Na₈(Al₆Si₆O₂₄)Cl₂; exact identification requires testing
Sea Glass (Teal/Turquoise)
Amorphous Silica (SiO2) with trace metal oxides
Sea Glass (Turquoise/Aqua)
Amorphous Silica (SiO2) with transition metal dopants
Diamond
Diamond (pure Carbon, C)
Rough Sapphire (Corundum)
Corundum (Al2O3)
Mother of Pearl (Nacre) / Shell Fragment
Biogenic Calcium Carbonate (Aragonite and Conchiolin)
Nephrite Jade
Ca2(Mg,Fe)5Si8O22(OH)2
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Chert (and/or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (variations include Flint/Jasper)
Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert / Jasper
Silicon Dioxide (SiO₂)
Chert (specifically Yellow/Brown Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone (Ferruginous)
Arenite (SiO2 with Fe2O3 inclusions)
Chert (often called Flint)
Chert (Cryptocrystalline Quartz, SiO2)
Goldstone (Red)
Aventurine Glass
Black Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Sandstone
Arenite (mostly SiO2)
Sandstone (Water-worn Cobble)
Arenite (SiO2 with CaCO3 or Fe2O3 cement)