Ironstone Concretion
Ironstone (Siderite/Goethite/Hematite matrix)
Category
Browse organic (geological relative) specimens identified by the Rock Identifier community.
Ironstone Concretion
Ironstone (Siderite/Goethite/Hematite matrix)
Sandstone
Sandstone (Quartz-rich Arenite / SiO2)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood / Chalcedony (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Fossil Shell (Bivalve)
Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal)
Chipped Glass/Plastic Fragment
Silicon dioxide (SiO2) for glass (amorphous) or various polymer compounds for plastic
Cat's Eye Moonstone (Simulated/Synthetic or natural Cat's Eye Quartz/Glass)
There is no single scientific name. The appearance suggests either: Moonstone (feldspar group), Cat's Eye Quartz (SiO2), Apatite (Ca5(PO4)3(F,Cl,OH)), or most likely a synthetic material such as Fiber Optic Glass or 'Opalite' (a type of glass).
Petrified Wood
Silicon Dioxide Fossilized Wood (SiO2)
Amber
Succinite / Fossilized Resin (C10H16O)
Chert (Flint) with Limestone Matrix
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
Limestone (Crushed Gravel)
Limestone (Calcium Carbonate, CaCO3)
Chert Nodule (with Geode cavity)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Geode (Unopened)
Silica-rich concretion (SiO2)
Chert (Jasper variation)
Silicon dioxide (SiO2) - Microcrystalline Quartz
Petrified Wood
Silicified wood (Quartz/Chalcedony/SiO2)
Fossiliferous Limestone
Biomicrite / Limestone with fossils
Fossilized Shark Tooth
Chondrichthyes (Class) fossil
Olive Sea Shell Fossil
Oliva sp. (Calcium Carbonate, CaCO3)
Rose Quartz
Quartz (SiO₂), specifically a variety of Quartz
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (and Fossilized Brachiopod shell)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (Flint Nodules)
Microcrystalline Quartz (SiO2)
Black Star Diopside (beads)
Diopside (CaMgSi2O6) - a member of the pyroxene group
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Petrified Wood
Silicified wood (Quartz variant, SiO2)
Chalcedony / Agate with Botryoidal Quartz
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Chert (specifically Gray/Blue Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Graphite Schist
C (Carbonaceous Schist)
Chert (Black Chert/Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert / Flint
Cryptocrystalline Quartz (Silicon Dioxide, SiO2)