Chert (Red Jasper variant)
Microcrystalline Quartz (SiO2)
Category
Browse organic (geological relative) specimens identified by the Rock Identifier community.
Chert (Red Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (specifically Yellow/Brown Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Pyrite-bearing Schist
Pyritic Quartz-Mica Schist with FeS2 inclusion
Chert (Jasper/Common Opal transition)
Microcrystalline Quartz (SiO2) with iron oxide inclusions
Chert (Flint variety)
Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2
Chert Nodule / Ironstone Concretion
Microcrystalline Quartz (SiO2) with Iron Oxides
Quartz
Silicon Dioxide (SiO2)
Quartz (likely a form of massive or vein quartz)
Quartz (SiO₂)
Honey calcite (orange calcite)
Calcite, calcium carbonate (CaCO₃)
Yellow calcite crystal
Calcite (CaCO₃), likely honey/yellow calcite
Fine-grained brown sand or weathered soil
Unconsolidated siliciclastic sediment, likely quartz-rich sand (SiO₂) mixed with iron-oxide-coated grains
Coquina Limestone (Fossiliferous Limestone)
Calcareous bioclastic sedimentary rock (CaCO3)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (Brown Variety)
Silicon dioxide (SiO2)
Chert (and its variety Flint)
Silicon Dioxide (SiO2) - Microcrystalline or cryptocrystalline Quartz
Coquina / Fossiliferous Limestone
Coquina (composed primarily of Calcium Carbonate / CaCO3)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone
Sandstone (Quartz-rich Arenite / SiO2)
Limestone
Calcium Carbonate (CaCO3)
Chert (likely flint), possibly chalcedony-rich
Microcrystalline quartz, SiO₂ (quartz/chalcedony)
Fossilized Brachiopod
Brachiopoda (e.g., Atrypa or Rhynchonellida)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood (Agatized/Silicified Wood)
Silicified Paleoxylon (primarily SiO2)
Ironstone Concretion
Ironstone (Siderite/Goethite/Hematite matrix)
Vesicular basalt (weathered scoriaceous basalt)
Basalt; chiefly plagioclase, pyroxene, and commonly olivine (approximately 45–52% SiO₂)
Petrified Wood
Silicon Dioxide (SiO2) permineralized organic matter
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Fossilized Bone
Vertebrate Fossil Fragment (Calcium Phosphate / Hydroxyapatite)
Petrified Wood
Silicified wood (primarily Quartz, SiO2)
Black Jasper
Black Jasper (Silicate mineral - SiO2)
Gastropod Steinkern (Fossil Snail Internal Mold)
Class Gastropoda (Internal Mold)
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).
Chert Nodule (with Geode cavity)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Weathered fossil fragment, possibly bone
Indeterminate fossilized bone; likely mineralized vertebrate bone (apatite-rich)