Limonite after Pyrite (Prophecy Stone or Ironstone Concretion)
Goethite/Limonite pseudomorph after Pyrite/Marcasite (FeO(OH)·nH2O)
Category
Browse metamorphic and sedimentary specimens identified by the Rock Identifier community.
Limonite after Pyrite (Prophecy Stone or Ironstone Concretion)
Goethite/Limonite pseudomorph after Pyrite/Marcasite (FeO(OH)·nH2O)
Magnetite (Lodestone variety)
Magnetite (Iron(II,III) oxide, Fe3O4)
Pyrite on Quartz
Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)
Pyrite in Matrix (Quartz/Schist)
Iron Sulfide (FeS2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Biotite (Mica)
Biotite group (K(Mg,Fe)3AlSi3O10(F,OH)2)
Almandine Garnet (weathered)
Almandine (Fe3Al2(SiO4)3)
Granite Gneiss
Gneiss (High-grade regional metamorphic rock)
Gneiss (Schistose)
Gneiss
Quartzite (Rounded Pebble)
Quartzite (predominantly SiO2)
Quartzite
Quartzite (primarily SiO2)
Gneiss (specifically a Granitic Gneiss)
Gneiss (Composition: Quartz, Feldspar, Mica)
Banded Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Biotite/Amphiboles)
Mica Schist with Iron Staining
Mica Schist
Petrified Wood
Silicified wood (Quartz, SiO2)
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Red Jasper (Banded Jasper)
Silicon Dioxide (SiO2) with Hematite impurities
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Gneiss
Gneiss
Quartzite
Quartzite (SiO2)
Zebra Marble
Metamorphosed Alabaster/Limestone (CaCO3)
Gneiss (specifically a Banded Gneiss cobble)
Gneiss (composed mainly of Quartz, Feldspar, and Biotite/Amphibole)
Blue Calcite
Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Pyrite on Quartz matrix
Iron Disulfide (FeS2) on Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal Fragments)
Silicon Dioxide (SiO2)
Calcite
Calcium Carbonate (CaCO3)
Gneiss (specifically a granitic gneiss cobble)
Gneiss (high-grade regional metamorphic rock)
Gneiss (specifically a Granitic Gneiss)
Gneiss (typically composed of Quartz, Feldspar, and Mica/Amphiboles)
Gneiss Pebble
Gneiss
Quartzite
Quartzite (primarily SiO₂)
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
Gneiss (specifically Biotite Gneiss)
Gneiss (high-grade metamorphic rock primarily composed of Silicates)
White Marble
Recrystallized Calcite (CaCO3)
Anthracite Coal
Anthracite
Aventurine (Green)
Silicon Dioxide (Quartz) with inclusions typically of Fuchsite; SiO2
Petrified Wood
Silicified Wood (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Jasper (Red Jasper)
Silicon Dioxide (SiO2) with Hematite inclusions