Fossilized Shark Tooth
Carcharhinus sp. (likely Bull or Requiem shark family)
Category
Browse mineral (chalcedony) specimens identified by the Rock Identifier community.
Fossilized Shark Tooth
Carcharhinus sp. (likely Bull or Requiem shark family)
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)
Quartz with mica and feldspar (Pegmatite fragment)
Granitic Pegmatite (composed mainly of SiO2 with KAlSi3O8)
Botryoidal Hematite (Iron Stone Conglomerate)
Hematite (Fe2O3) in sedimentary matrix
Sandstone (likely Arkosic or Quartzose)
Arenite (SiO2 based with mineral inclusions)
Garnet (Almandine/Pyrope series)
Silicate mineral (Almandine: Fe3Al2Si3O12; Pyrope: Mg3Al2Si3O12)
Hematite
Iron(III) oxide (Fe2O3)
Peacock Ore (Bornite or Chalcopyrite)
Bornite (Cu₅FeS₄) or iridescent Chalcopyrite (CuFeS₂)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Milky Quartz with Chlorite/Epidote inclusions
Silicon Dioxide (SiO2) with phyllosilicate/sorosilicate inclusions
Red Sandstone
Arenite with iron oxide (Hematite) cement
Sandstone with Iron Oxide Staining
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
Red Sandstone
Arenite (primarily Quartz with Hematite cement)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 cement)
Red Sandstone
Clastic sedimentary rock (primarily SiO2 with Fe2O3)
Malachite
Copper carbonate hydroxide Cu2CO3(OH)2
Sandstone (Ferruginous)
Arenite (Fe-rich)
Black Marble
Recrystallized Calcite (CaCO3)
Turquoise (Blue Howlite / Magnesite imitation)
CuAl6(PO4)4(OH)8·4H2O (for natural Turquoise); Ca2B5SiO9(OH)5 (for Howlite)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 oxides)
Red Sandstone
Arenite (with Iron Oxide)
Sandstone (Red Sandstone)
Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide)
Magnetite (Lodestone variety)
Magnetite (Iron(II,III) oxide, Fe3O4)
Quartz-bearing Ore (likely Gold-bearing Quartz)
Quartz (SiO2) with potential sulfide mineralization (Pyrite/Arsenopyrite)
Granite
Granite (Phaneritic igneous rock)
Sandstone
Sandstone (Silicon Dioxide, SiO2)
Howlite
Howlite (Ca2B5SiO9(OH)5)
River/Stream Pebble
Clast / Detrital Grain / Rounded Sedimentary Particle (Compositionally variable, commonly Quartz, Feldspar, Chert, or other resistant rock fragments)
Schist
Schist (various compositions)
Andesite Porphyry (Geological Drill Core)
Andesite Porphyry
Jasper
Silicon dioxide (Microcrystalline Quartz, SiO2)
Tiger's Eye
Fibrous Quartz (SiO2) with iron inclusions
Chert (Flint Pebbles)
Microcrystalline Quartz (SiO2)
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Quartz (Citrine variety)
Silicon Dioxide (SiO2)
Prehnite
Prehnite, Ca2Al2Si3O10(OH)2
Amazonite
Microcline (KAlSi3O8) with Pb impurities
Citrine
Silicon dioxide (SiO2)
Amethyst
Quartz (Silicon Dioxide with Iron impurities), SiO2
Amazonite
KAlSi3O8 (Potassium aluminum silicate - blue-green variety of Microcline)
Fire Opal (in Matrix)
Hydrated Silica (SiO2·nH2O)