Pyritic Mudstone
Argillaceous rock (FeS2)
Category
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Pyritic Mudstone
Argillaceous rock (FeS2)
Chert Concretion (Flint)
Silicon Dioxide (SiO2)
Chert (Quartz Variety)
Chert (Silicon Dioxide, SiO2)
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Note: Item is not a geological specimen
n/a
Amber
Succinicum (C10H16O)
Chert (Jasper/Agate)
Silicon Dioxide (SiO2)
Chert / Jasper / Agate (Chalcedony Group)
Microcrystalline Quartz (SiO2)
Chert
Chert (SiO2)
Fossiliferous Limestone
Sedimentary rock containing Indeterminate Fossil remains (likely Crinoid stem or Bryozoan fragment)
Chert (Jasper-like Silicate)
Microcrystalline Quartz (SiO2)
Chert Concretion / Nodule
Microcrystalline Quartz (SiO2)
Fossilized Coral
Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)
Fossilized Bone Fragment
Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Graphite-rich metamorphic rock (graphitic schist)
Graphitic schist; chiefly graphite (C), quartz (SiO₂), and mica minerals
Ironstone Concretion (Limonite/Goethite)
Goethite/Limonite concretion (FeO(OH)·nH2O)
Lapis Lazuli
Lazurite-dominant rock, (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Chert (Cryptocrystalline Silicon Dioxide, SiO2)
Chert (Gravel)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclastic Inclusions
Black Limestone with Calcite Veins
Limestone (Calcium Carbonate, CaCO3)
Silty Shale or Mudstone
Siltstone/Mudstone (Clastic Sedimentary Rock)
Chert (Jasper/Flint Pebble)
Microcrystalline quartz (SiO2)
Lapis Lazuli
Lapis Lazuli (Mineral composition: Lazurite (Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2, Calcite, and Pyrite)
Petrified Wood
Silicified Wood (primarily SiO₂ / Silicon Dioxide)
Concrete or asphalt-like aggregate surface with a dark fragment
Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock
Chert (Brown Variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Fossilized Wood (Petrified Wood)
Agatized wood (primarily SiO2)
Fossilized tooth, likely a mammalian tooth fragment
Indeterminate fossil tooth; possibly an ungulate or carnivoran tooth
Fossiliferous Sandstone
Sedimentary rock containing invertebrate fossils
Chert Nodule / Flint
Microcrystalline Quartz (SiO2)
Jasper
Microcrystalline Quartz (SiO2)
Carved red coral bead (likely coral or coral-colored resin)
Corallium spp. (precious coral; calcium carbonate, CaCO₃)
Fossilized Shark Tooth (Fragment)
Elasmobranchii gen. et sp. indet. (Calcium Phosphate / Apatite fossil)
Chert (often called Flint in dark varieties)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Shark Tooth Fossil
Vertebrate fossilized tooth
Limestone with Lichen
Carbonate Sedimentary Rock (primarily CaCO3)
Chert (often called Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper
Silicon dioxide (SiO2)