Limestone
Calcium Carbonate (CaCO3)
Category
Browse sedimentary rock (technically a variety of chalcedony) specimens identified by the Rock Identifier community.
Limestone
Calcium Carbonate (CaCO3)
Vesicular Basalt
Mafic Igneous Rock
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily Quartz, SiO2)
Sandstone
Arenite
Milky Quartz
Silicon Dioxide (SiO2)
Granite Pebble (Salt and Pepper Granite)
Felsic Intrusive Igneous Rock (Granite)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Basalt
Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Sandstone
Arenite (SiO2 based with primary clasts 0.0625 to 2 mm)
Sandstone
Arenite (primarily SiO2)
Sandstone (Ferruginous)
Arenite (Fe-rich)
Sandstone (with potential trace fossils)
Clastic sedimentary rock (primarily SiO2)
Collection of Minerals and Ores
Various (e.g., Uraninite (U3O8), Carbon (C), Native Gold (Au), Hematite (Fe2O3), Galena (PbS), etc.)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Sandstone
Arenite (primarily SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone (Gneissic or Banded)
Clastic Sedimentary Rock (composed predominantly of SiO2)
Quartzite
Quartzite
Quartz (likely Herkimer Diamond style)
Silicon Dioxide (SiO2)
Manganese Oxide Crust on Limestone
Manganese Oxides (e.g., Pyrolusite MnO2 or Romanechite) on CaCO3
Sandstone (likely Arkosic or Quartzose)
Arenite (SiO2 based with mineral inclusions)
Druzy Quartz
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Ammonite Fossil
Ammonoidea (subclass)
Basalt with Phenocrysts (Porphyritic Basalt)
Porphyritic Basalt (primarily Plagioclase and Pyroxene)
Sandstone (Banded)
Clastic sedimentary rock (primarily SiO2)
Clear Quartz Crystal
Quartz (Silicon Dioxide, SiO2)
Ferruginous Sandstone (Ironstone)
Sandstone with Hematite/Goethite cement (SiO2 + FeO(OH))
Sandstone
Arenite (composed primarily of SiO2)
Gneiss
Foliated Metamorphic Rock (Gneiss)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with iron oxide cement)
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Sandstone (Banded)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (Ferruginous)
Arenite (with iron oxide cement, Fe2O3)
Sandstone (Ferruginous)
Arenite (with high iron oxide content)
Sandstone Pebble
Arenite (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Yellow Ochre / Limonite
Limonite (FeO(OH)·nH2O)