Chert
Microcrystalline Quartz (SiO2)
Category
Browse organic (geological interest) specimens identified by the Rock Identifier community.
Chert
Microcrystalline Quartz (SiO2)
Chert
Cryptocrystalline Quartz (SiO2)
Limestone with Fossil Fragment
Sedimentary carbonate rock (CaCO3)
Fossilized Plant or Tree Bark
Lepidodendron or Sigillaria (example genera)
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
Sandstone
Arenite
Chert (Jasper/Flint variant)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert (variations include Flint)
Silicon Dioxide (SiO2)
Black Jasper (Etched)
Silicon Dioxide (SiO2) with impurities
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert with Limestone matrix
Microcrystalline silica (SiO2) in Calcite (CaCO3) matrix
Fossiliferous Rock (Invertebrate Fossil in Matrix)
Fossiliferous limestone or shaly matrix containing skeletal fossil remains
Concretion
Septarian Concretion (Fragmentary)
Jasper
Microcrystalline Quartz (SiO2)
Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
Chert (Flint variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Jasper
Silicon dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)
Grass (Organic Matter/Soil)
Poaceae (family of monocotyledonous flowering plants)
Pink Coral
Corallium rubrum (or related species, composed of calcium carbonate)
Petrified Wood
Silicified wood (SiO2)
Fossiliferous Kalkstein (Marl/Sandstone)
Fossiliferous calcarenite/siltstone
Amygdaloidal Basalt with Secondary Minerals
Basalt containing secondary mineralization (likely Chlorite, Celadonite, or Zeolites)
Quartz (likely a weathered/tumbled piece)
Quartz (SiO₂)
Unknown Organic Object (likely a berry or fruit)
Not applicable; this is not a geological specimen. If it were a cranberry, its scientific name would be Vaccinium macrocarpon; if a cherry, it would be Prunus avium or Prunus cerasus.
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Chert / Jasper
Cryptocrystalline Silica (SiO2)
Chert (Flint)
Microcrystalline Quartz or Cryptocrystalline Silica (SiO2)
Chert (Flint)
Microcrystalline Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Fossilized Horn Coral
Order Rugosa (Rugose Coral)
Chert (Flint variety)
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Chert (Light Variety)
Sedimentary cryptocrystalline quartz (SiO2)
Fossiliferous Limestone
Calcite (CaCO3) with Bioclastic inclusions
Chert / Flint
Chert (Cryptocrystalline Quartz, SiO2)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Black Jasper
Silicon Dioxide (SiO2) with impurities