Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Category
Browse organic (mineraloid) specimens identified by the Rock Identifier community.
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Fossilized Shark Tooth
Carcharhinus sp. (likely Bull or Requiem shark family)
Ironstone Concretion
Siderite or Goethite Concretion
Fossilized Echinoid (Sea Urchin)
Echinoidea (Class) - Often found as Micraster or Clypeaster specimens
Fossiliferous Limestone
Fossiliferous Limestone (CaCO3)
Chert (River Pebble)
Chert (Silicon Dioxide, SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert / Flint Pebble
Silicon Dioxide (SiO2)
Chert (River Pebble)
Microcrystalline silica (SiO2)
Fossiliferous Limestone
Biogenic Limestone (CaCO3)
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone (Crinoid stem)
CaCO3 (Calcium Carbonate) with Fossil Inclusions
Chert (River Pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Black Chert/Flint)
Microcrystalline quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert (Limestone-based)
Silicon dioxide (SiO2)
Chert (Arrowhead Preform or Flake)
Microcrystalline Quartz (SiO2)
Chert (Flint nodule)
Chert (SiO2)
Graphite
Graphite (Chemical Formula: C)
Chert (Chert / Flint)
Silicon dioxide (SiO2) - Microcrystalline quartz
Chert (White-Tan variety)
Silicon dioxide (SiO2) / Microcrystalline Quartz
Chert (Nodular or Fossiliferous)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Arrowhead Fragment)
Microcrystalline Quartz (SiO2)
Chert (with Quartz vein/coating)
Microcrystalline Quartz (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (Tan/Yellow variety)
Microcrystalline quartz (SiO2)
Chert / Flint
Chert (Silicon Dioxide, SiO2)
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
Chrysanthemum Stone
Celestine (SrSO4) or Calcite (CaCO3) in Limestone/Porphyry matrix
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (variously known as Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Chert (Silicon Dioxide, SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (and Flint)
Microcrystalline Silica (SiO2)
Chert (variant Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Chert (or Flint)
Chert (Sedimentary Cryptocrystalline Sio2)
Chert (Quartz Variety)
Chert (Silicon Dioxide, SiO2)
Chert (Jasper variety)
Chert (Silicon Dioxide, SiO2)
Fossilized Coral
Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)