Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
sedimentary
Category
Organic Mineral
Browse organic mineral specimens identified by the Rock Identifier community.
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
mineral
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Amygdaloidal Basalt with Epidote/Chlorite
Basalt (containing (Ca2(Al2Fe3+)(SiO4)(Si2O7)O(OH)))
igneous
Limonite (Ironstone)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
mineral
Banded Gneiss
Gneiss (pronounced 'nice')
metamorphic
Limonite Sandstone
Ferruginous Sandstone (Hydrated Iron Oxide)
sedimentary
Epidote
Epidote ({Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
mineral
Epidote
{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
mineral
Limonite (Yellow Ochre)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
mineral
Amygdaloidal Basalt with Secondary Minerals
Basalt containing secondary mineralization (likely Chlorite, Celadonite, or Zeolites)
igneous
Limonite
Limonite (Hydrous iron oxides, predominantly Goethite FeO(OH)·nH2O)
mineral
Magnetite
Magnetite (Fe3O4)
mineral
Epidote
Epidote (Ca2(Al2,Fe3+)AlSi3O12(OH))
mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Greisen
Greisen
Metamorphic
Greisen (Quartz-Muscovite-Turretine Rock)
Greisen
Metamorphic Rock
Rainbow Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Vanadinite
Lead Chlorovanadate, Pb5(VO4)3Cl
mineral
Nickel coin (U.S. currency)
Cupronickel (75% Copper, 25% Nickel alloy)
man-made alloy (metallic)
Schist
Mica Schist
metamorphic
Boxwork Siderite or Sepatarian Nodule Weathering
Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment
sedimentary
Schist
N/A (a rock type, not a mineral formula)
metamorphic
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Granite
Granite (Felsic Plutonic Rock)
igneous
Fluorite with Quartz coating
Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)
mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
igneous
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Peacock Ore
Bornite (Cu5FeS4) or iridescent Chalcopyrite (CuFeS2)
mineral
Granite
Phaneritic plutonic rock (Quartz, Alkali Feldspar, and Plagioclase)
igneous
Green Fluorite (likely synthetic or heat-treated for jewelry)
Calcium Fluoride (CaF2)
mineral
Sandstone
Arenite (SiO2 based with various mineral cements)
sedimentary
Limonite (Oxidized Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Limonite/Goethite Nodule
Iron Oxyhydroxide (primarily FeO(OH)·nH2O)
mineral
Limonite (Yellow Ochre)
Hydrated iron(III) oxide-hydroxides (FeO(OH)·nH2O)
mineral
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
mineral
Bauxite
Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)
sedimentary
Granite
Granite (Felsic Intrusive Igneous Rock)
igneous
Sandstone (Ferruginous)
Arenite (Fe2O3 staining)
sedimentary
Diorite (River Rock/Cobble)
Intermediate Plutonic Igneous Rock (Diorite)
igneous
Gneiss
Gneiss (High-grade regional metamorphic rock)
Metamorphic