Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Category
Browse sedimentary (fossilized) specimens identified by the Rock Identifier community.
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Quartz Geode with Calcite
Silicon Dioxide (SiO2) and Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Agate
Banded Chalcedony (SiO2)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)
Orange Calcite
Calcium Carbonate (CaCO3)
Blue Chalcedony (likely dyed Agate)
Silicon Dioxide (SiO₂)
Iron Ore (Limonite and Hematite)
Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Marble
Recrystallized Calcite (CaCO3)
Magnetite
Iron(II,III) oxide (Fe3O4)
Flint (Chert)
Silicon Dioxide (SiO2)
Mica Schist (with Muscovite)
Muscovite/Quartz Schist (KAl2(AlSi3O10)(OH)2)
Pyrite
Iron Disulfide (FeS2)
Hematite Nodule
Hematite (Fe2O3)
Ironstone (likely Limonite or Goethite)
Ferruginous sedimentary rock (FeO(OH)·nH2O)
Banded Jasper (Chert)
Silicon Dioxide (SiO2) - variety of Chalcedony
Ironstone with Limonite/Goethite coating
Ferruginous Sedimentary Rock (contains Limonite FeO(OH)·nH2O)
Quartz (Druzy)
Silicon Dioxide (SiO2)
Banded Siltstone or Argillite
Siltstone (primarily SiO2 with Al and Fe oxides)
Quartz River Cobble
Silicon Dioxide (SiO2)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Sandstone with Manganese Dendrites/Oxide coatings
Arenite with Pyrolusite and Romanechite (MnO2)
Yellow Quartzite (River Stone)
Quartzite (primarily SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (varieties include Flint and Mudstone)
Microcrystalline Silica (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Conglomerate
Conglomerate (SiO2, Al2O3, Fe2O3, CaCo3)
Chert / Flint
Chert (Cryptocrystalline Silica, SiO2)
Riverstone Jasper (Chert variant)
Silicon Dioxide (SiO2)
Piddock bored rock (Boring Stone)
Ichnofossil-bearing Limestone or Mudstone (trace fossils by Pholadidae)
Chert (Jasper)
Microcrystalline Quartz (SiO2) with iron oxide impurities
Brain Coral Fossil
Family Mussidae or Merulinidae (Order Scleractinia)
Concretion
Septarian concretion (likely containing Calcite or Siderite)
Sandstone (Stream Pebble)
Arenite (primarily SiO2)
Chert (Field Stone/Pebble)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Brachiopod Fossil in Shale
Phylum Brachiopoda (often species of Order Spiriferida or Rhynchonellida)
Chert (Jasper)
Silicon Dioxide (SiO2)
Ferruginous Sandstone (Gritstone)
Clastic sedimentary rock with iron-rich cement (FeO(OH)·nH2O)