Banded Gneiss
Gneiss (quartz-feldspar-biotite metamorphic rock)
Category
Browse sedimentary rock (altered) specimens identified by the Rock Identifier community.
Banded Gneiss
Gneiss (quartz-feldspar-biotite metamorphic rock)
Chert (Jasper)
Silicon dioxide (SiO2)
Arkosic Sandstone
Arkose
Red Sandstone
Arenite (Ferruginous Sandstone)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (primarily Quartz, SiO2)
Gastropod Steinkern (Fossilized Snail Cast)
Phylum Mollusca, Class Gastropoda (Commonly CaCO3 or SiO2 after replacement)
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Nuummite
Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)
Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)
Chert (microcrystalline quartz)
Sandstone with Quartz Veining
Arenite with hydrothermal quartz (SiO2)
Chert (often called Jasper in this color)
Microcrystalline quartz (SiO2)
Chert (White/Gray variety)
Chert (SiO2)
Fossiliferous Limestone with Brachiopods
Calcium Carbonate (CaCO3) with fossilized Brachiopoda sp. (likely Order Spiriferida or Rhynchonellida)
Ferruginous Chert (Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Oolite (Ooid Limestone)
Ooidal Limestone (comprised of CaCO3)
Coquina
Coquina (Bioclastic Limestone)
Crinoid Fossil Stem Segment
Class Crinoidea (Echinodermata)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Fossilized Coral (Petoskey-like or Favosites)
Anthozoa (Fossilized Coral)
Banded Chert
Microcrystalline silicon dioxide (SiO2)
Ferruginous Sandstone (Ironstone)
Ferruginous Sandstone / Limonite-cemented Quartz Sandstone
Sandstone (with possibly iron oxides and other minerals)
Sandstone
Quartz (likely Milky Quartz)
Quartz (SiO₂ - Silicon Dioxide)
Hematite
Iron(III) oxide (Fe2O3)
Gneiss
Gneiss (High-grade metamorphic rock)
Chalcedony in Matrix
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variation)
Chert (SiO2)
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Septarian Nodule
Septarian Nodule (Mixture of Calcite, Aragonite, and Limestone/Clay)
Sandstone (Quartzose Sandstone)
Arenite (SiO2)
Pyrite Geode (Sparkling Druzy)
Iron Sulfide (FeS2) in Sedimentary Nodule
Chert (often called Jasper or River Rock)
Chert (SiO2)
Banded Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Jasper with Quartz inclusions
Silicon Dioxide (SiO2) - Microcrystalline Chalcedony
Red Jasper
Jasper (Silicon Dioxide, SiO2 with Iron Oxide impurities)
Jasper / Chert (River Pebble)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Jasper with Hematite inclusions
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)
Tufa (Limestone)
Calcareous Tufa (CaCO3)
Red Sandstone
Arenite (Ferruginous Sandstone)
Jasper (likely Lake Superior Jasper)
Jasper (Silicon Dioxide, SiO2)