Sandstone
Arenite (compositionally various, primarily SiO2)
Category
Browse sedimentary (with some aspects of mineral replacement) specimens identified by the Rock Identifier community.
Sandstone
Arenite (compositionally various, primarily SiO2)
Gneiss
Gneiss
Chert (often called Flint in this context)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Fossil Coral
Fossilized Scleractinia or Tabulata (various genera/species)
Banded Agate
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with iron oxide cement)
Petrified Wood
Silicified Wood (SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Galena
Lead Sulfide (PbS)
Sandstone
Arenite
Conglomerate
Conglomerate (clastic sedimentary rock)
Red Sandstone
Arenite (primarily Quartz with Hematite cement)
Chert / Flint
Microcrystalline Quartz (SiO2)
Geode (Quartz)
Silicon Dioxide (SiO2)
Gneiss (with Quartz-Feldspar vein)
Gneiss (high-grade metamorphic rock) containing Quartz (SiO2) and Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Gneiss (Banded Gneiss)
Gneiss
Sphalerite
Zinc sulfide (Zn, Fe)S
Likely chert or flint
Microcrystalline quartz (SiO₂), commonly called chert; exact identification requires testing
Chert (Flint)
Silicon dioxide (microcrystalline quartz, SiO2)
Chert (Agatized)
Silicon Dioxide (SiO2)
Chert (specifically Flint or Jasper-Chert)
Silicon Dioxide (SiO2)
Jasper
Silicon dioxide (SiO2)
Chert Nodule
Microcrystalline Quartz (SiO2)
Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Sandstone
Arenite (Clastic Sedimentary Rock)
Vuggy Limestone
Calcium Carbonate (CaCO3) with Quartz/Calcite inclusions
Sandstone (Ferruginous Concretion)
Arenite (with iron oxide cement)
Pyrite
Iron Sulfide (FeS2)
Sandstone (Arkose/Quartzose)
Arenite (SiO2 based clastic rock)
Rhodonite
Rhodonite (Manganese Iron Magnesium Calcium Silicate - (Mn,Fe,Mg,Ca)SiO3)
Tiger's Eye (with Blue Tiger's Eye / Hawk's Eye)
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Ironstone
Ferruginous Sedimentary Rock (composed of Goethite, Hematite, and Limonite)
Gneiss
Gneiss
Granite Gneiss
Gneiss (High-grade metamorphic rock)
Fossiliferous Limestone (Coquina)
Calcite (CaCO3) with Bioclastic inclusions
Ferruginous Sandstone
Iron-rich Clastic Sedimentary Rock
Gneiss
Gneiss (High-grade metamorphic rock)