Obsidian
Obsidian (volcanic glass, amorphous silica rich rock)
Igneous
Category
Man Made Rock (Sedimentary Analogue)
Browse man made rock (sedimentary analogue) specimens identified by the Rock Identifier community.
Mudstone
Lutylite (group of fine-grained sedimentary rocks)
sedimentary
Shale (Ferruginous)
Laminated Mudrock (Siliciclastic Sedimentary Rock)
sedimentary
Sandstone (Ferruginous)
Arenite (Siliclastic Sedimentary Rock)
sedimentary
Serpentinite
Serpentinite (composed primarily of serpentine-group minerals like antigorite, chrysotile, and lizardite; chemical formula varies but generally Mg3Si2O5(OH)4)
Metamorphic Rock
Sandstone
Sandstone (clastic sedimentary rock)
Rock
Quartz Geode
Silicon Dioxide (SiO2) within a geode
mineral
Quartz (Engineered Quartz Surface)
Silicon Dioxide (SiO2) based composite
mineral (man-made composite)
Red Slag Glass (Cullet)
Amorphous Silicon Dioxide (SiO2) with metallic dopants
Antropogenic (Man-made material)
Faceted Glass (Costume Jewelry)
Amorphous Silicon Dioxide with colorants (Glass)
Synthetic/Man-made Material
Sandstone
Arenite (primarily SiO2)
sedimentary
Quartz Geode (likely within Limestone or Dolomite matrix)
Quartz (SiO₂)
Mineral within a Sedimentary Rock
Sandstone
Arenite (SiO2 based with various mineral cements)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone
Arenite (predominantly SiO2 quartz grains)
sedimentary
Sandstone
Arenite (SiO2 principal)
sedimentary
Conglomerate
Conglomerate (Detrital Sedimentary Rock)
sedimentary
Amber-bearing Coal/Sedimentary Rock
Bituminous coal or carbonaceous siltstone with Fossilized Tree Resin (C10H16O)
sedimentary
Lapis Lazuli
Lapis Lazuli (Complex rock consisting primarily of Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2)
metamorphic
Chert (Jasper/Flint variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Green Banded Chert (Agate/Jasper)
Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite
sedimentary
Chert (Flint variety)
Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2
sedimentary
Sandstone (lithic)
Lithic Wacke / Arenite
sedimentary
Chert (Yellow/Tan Variety)
Chert (SiO2)
sedimentary
Synthetic Costume Accessory (Non-Geological)
Polyester and Acrylic Fiber (Anthropogenic polymer)
Synthetic / Man-made textile
Sea Glass (Cobalt Blue)
Amorphous Silica (Glass with Cobalt additives)
Anthropogenic specimen (man-made)
Blue Goldstone
Aventurine Glass (Silicon Dioxide infused with Cobalt/Copper)
Synthetic (Man-made Glass)
Porcelain (Kaolin-based)
Alumina silicate ceramic (composed primarily of Kaolinite: Al2Si2O5(OH)4)
metamorphic (man-made/engineered)
Sandstone (with potentially high Feldspar/Arkose content)
Clastic sedimentary rock (SiO2 dominated)
sedimentary
Shale
Shale (Consolidated fine-grained clay/silt)
sedimentary
Chert (and Flint)
Silicon Dioxide (SiO2)
sedimentary
Chert (specifically White Chert or Novaculite)
Silicon Dioxide (SiO₂)
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (SiO2 with Fe2O3 oxides)
sedimentary
Sandstone
Arenite (primarily composed of SiO2)
sedimentary
Sandstone or Limestone
Arenite or Calcareous Sedimentary Rock
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Chert (Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone (Ferruginous)
Arenite (SiO2 with iron oxide impurities)
sedimentary
Claystone Concretion
Septarian Concretion (Ironstone-rich)
sedimentary
Sandstone (Ferruginous)
Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)
sedimentary
Gastropod Steinkern (Internal Mold Fossil)
Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix
sedimentary