Limonite
Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)
Category
Browse sedimentary (secondary mineral formation) specimens identified by the Rock Identifier community.
Limonite
Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)
Travertine
Travertine (CaCO3 - Calcium Carbonate)
Jasper (Iron-rich Chalcedony)
Jasper (Microcrystalline Silicon Dioxide, SiO2 plus iron oxide impurities)
Jasper (specifically Bloodstone/Heliotrope or Dark Green Jasper)
Cryptocrystalline Quartz (SiO2) with inclusions
Banded Iron Formation
Banded Iron Formation (BIF)
Stromatolite
Cyanobacteria fossilized formation (CaCO3)
Banded Iron Formation (BIF)
Magnetite-hematite-chert formation
Gowganda Tillite (Puddingstone)
Glacial Diamictite (Gowganda Formation)
Hematite
Iron(III) oxide (Fe2O3)
Magnetite / Iron Ore
Magnetite (Fe3O4)
Hematite
Iron(III) oxide (Fe2O3)
Pyrite
Iron Sulfide (FeS2)
Red Sandstone
Arenite (with Iron Oxide)
Amygdaloidal Basalt
Basalt with secondary mineral infilling
Sandstone
Clastic Sedimentary Rock (primarily Quartz, SiO2)
Quartz Druze on Matrix
Silicon Dioxide (SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Pyrite
Pyrite (FeS₂)
Carnelian Agate
Carnelian (Silicon Dioxide: SiO2) with iron oxide impurities
Blue-dyed Quartz Druzy
Silicon Dioxide (SiO2) with artificial pigment
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Pink Dyed Agate (Pink Agate Slice)
Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz
Botryoidal Goethite on Quartz
Goethite (α-Fe3+O(OH)) on Quartz (SiO2)
Sandstone
Arenite (primarily SiO2 - Silicon Dioxide)
Sandstone (Red)
Arenite (primarily Quartz, SiO2, with Iron Oxide cement)
Red Sandstone
Arenite (Ferruginous Sandstone)
Sandstone
Clastic Sedimentary Rock (composed primarily of Quartz, SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2) with various iron-oxide inclusions
Limestone
Calcium Carbonate (CaCO3)
Ammonite Fossil
Ammonoidea (subclass)
Sandstone (Ferruginous)
Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)
Sandstone (Ferruginous)
Arenite (Fe-rich)
Granite (weathered/river-tumbled)
Granite (Plutonic Igneous Rock)
Amygdaloidal Basalt
Basalt with secondary mineral infilling
Yellow Ocher / Limonite
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)
Botryoidal Chalcedony with Calcite
Chalcedony (SiO2 with accessory minerals, likely CaCO3)
Jasper
Jasper (Silicon Dioxide, SiO2)
Erythrite
Erythrite (Cobalt Bloom) - Co3(AsO4)2·8H2O
Sandstone
Arenite (primarily composed of SiO2 - Silicon Dioxide)
Gneiss (specifically a weathered Amphibolite or Garnet Gneiss)
Gneiss (complex silicate composition)