Ironstone Concretion (Limonite/Goethite)
Iron-rich sedimentary rock (FeOx)
Category
Browse mineral like (anthropogenic) specimens identified by the Rock Identifier community.
Ironstone Concretion (Limonite/Goethite)
Iron-rich sedimentary rock (FeOx)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Yellow Jasper
Silicon Dioxide (SiO2) with Goethite/Iron inclusions
Glauconite (Green Sandstone)
Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2
Fossil Shark Tooth
Selachimorpha (Chondrichthyes dental fossil)
Blue Quartz (or Blue Aventurine)
Silicon Dioxide (SiO2) with inclusions (typically Crocidolite or Dumortierite)
Quartz with inclusions
Silicon Dioxide (SiO2)
Greenschist (or Serpentinite) with Quartz-Feldspar Vein
Metabasalt / Greenschist Facies Rock
Quartz Pebble
Silicon Dioxide (SiO2)
Chrysocolla
Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Hematite
Hematite (Iron(III) oxide, Fe2O3)
Petrified Wood
Silicified wood (primarily SiO2)
Fluorite
Calcium Fluoride (CaF2)
Fossilized Bone
Permineralized Bone (Vertebrate Fossil)
Brachiopod Fossil
Phylum Brachiopoda
Coprolite
Coprolite (fossilized feces)
Quartz-Mica Schist (with Muscovite)
Metamorphic Rock (Quartz, Muscovite, Feldspar)
Chert (Flint variety)
Chert (Cryptocrystalline variety of Quartz, SiO2)
Ferruginous Sandstone Concretion (Ironstone Phosphorite)
Ferruginous Sandstone (variable Fe-oxide/hydroxide composition)
Garnet Schist
Almandine-Garnet Schist
Dendritic Chert
Silicon Dioxide with Manganese Oxide Inclusions (SiO2 + MnO2)
Obsidian
Volcanic Glass (Amorphous SiO2)
Sandstone (with Limonite/Iron Staining)
Arenite (SiO2 based) with FeO(OH) staining
Magnetite
Magnetite (Iron(II,III) oxide, Fe3O4)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3/FeO(OH) cementing agents)
Stalagmite (Flowstone)
Speleothem (Calcium Carbonate, CaCO3)
Eclogite (retrograded)
Eclogite (Omphacite-Garnet rock)
Schist
Mica Schist (primarily consisting of muscovite KAl2(AlSi3O10)(OH)2 or biotite K(Mg,Fe)3(AlSi3O10)(OH)2)
Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Quartz Pebble
Silicon Dioxide (SiO2)
Opalite
Synthetic Opalized Glass / Man-made Glass
Bivalve Fossil (Clam)
Class Bivalvia, likely Mercenaria or similar genus
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
Agate (Sliced and Carved)
Silicon Dioxide (SiO2) - Banded Chalcedony
Moss Agate
Silicon Dioxide with inclusions (SiO2)
Moss Agate
SiO2 with impurities (Chalcedony)
Quartz (or Chert/Flint)
Silicon Dioxide (SiO2)
Quartz Geode
Crystalline Silver Oxide (SiO2) in Calcareous Host
Almandine Garnet
Almandine, Fe3Al2(SiO4)3
Amygdaloidal Basalt
Vesicular Basalt with secondary mineral infilling (commonly Zeolites, Calcite, or Quartz)