Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper
Silicon dioxide (SiO2)
Black Jasper (Black Onyx substitute)
Silicon Dioxide (SiO2) with carbonaceous impurities
Chert (specifically Jasper/Brown Chert)
Silicon Dioxide (SiO2)
Limestone Pebble
Sedimentary carbonate rock (CaCO3)
Chert Nodules in Limestone
Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)
Basaltic Tuff / Volcanic Breccia
Pyroclastic Breccia / Lithic Tuff
Amber
Succinite (formula varies, primarily C10H16O)
Banded Limestone
Calcareous sedimentary rock (CaCO3)
Limestone with Iron Oxide Staining
Sedimentary Rock (Calcite, CaCO3)
Chert (Iron-stained)
Chert (SiO2)
Chert Concretion / Nodule
Microcrystalline Quartz (SiO2)
Geode (Unopened)
SiO2 (Quartz-filled Sedimentary Nodule)
Limestone or Sandstone Cobble
Sedimentary rock (Calcium carbonate or Quartz based)
Black Limestone with Calcite Veins
Limestone (Calcium Carbonate, CaCO3)
Sandstone with Quartz Crystal Infill
Quartz-cemented quartz arenite
Fossiliferous Limestone / Petrifaction
Sedimentary rock with fossil inclusions / Calcium Carbonate (CaCO3)
Red Jasper with Quartz
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
Fossilized Shark Tooth
Chondrichthyes (Class)
Fossilized Shark Tooth
Chondrichthyes tooth
Note: Item is not a geological specimen
n/a
Chert / Chalcedony
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Fossilized tooth, likely a mammalian tooth fragment
Indeterminate fossil tooth; possibly an ungulate or carnivoran tooth
Petrified Wood
Silicified Wood (Quartzo-feldspathic fossil wood)
Sandstone (Ferruginous)
Clastic Sedimentary Rock (Sandstone)
Sandstone (Pebble/Cobble)
Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)
Chert (Common Opal or Agate)
Microcrystalline Quartz (SiO2)
Chert (Jasper type)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone with Rugose Coral
Calcite (CaCO3) matrix containing Rugosa (order of extinct solitary and colonial corals)
Poppy Jasper
Microcrystalline Quartz (SiO2) with mineral inclusions
Chert (specifically Jasper/Flint)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Fossiliferous Limestone / Fossil Fragment
Calcium Carbonate (CaCO3) with indeterminate biogenic remains
Chert (and Flint)
Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Flint)
Chert (SiO2)
Chert (Jasper variation)
Silicon Dioxide (SiO2)
Chert (Polished/Tumbled)
Silicon Dioxide (SiO2)