Ironstone Concretion
Siderite or Limonite Concretion
Category
Browse mineral, sediment specimens identified by the Rock Identifier community.
Ironstone Concretion
Siderite or Limonite Concretion
Puddingstone
Conglomerate
Jasper (Cream/Yellow variety)
Silicon dioxide (SiO2)
Pyrite in Shale
Iron Disulfide (FeS2) in Argillaceous Shale
Chert Nodules (with Gryphaea or Shell inclusions)
Microcrystalline Quartz (SiO2) with Calcitic inclusions
Black Jasper
Jasper (Silicon Dioxide, SiO2)
Shale
Fissile mudstone (rich in clay minerals and quartz)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Ironstone Concretion (likely)
Goethite/Hematite/Limonite cemented sediment
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2)
Quartz (Milky/Cloudy Variety)
Silicon Dioxide (SiO2)
Staurolite (Fairy Stone)
Staurolite (Fe2+2Al9Si4O23(OH))
Shale or Siltstone
Sedimentary Rock (Siliciclastic)
River Stone (likely Siltstone or fine-grained Basalt)
Clastic Sedimentary (Siltstone) or Mafic Igneous (Basalt)
Sandstone
Clastic Sedimentary Rock (composed primarily of Quartz: SiO2)
Glauconitic Sandstone
Glauconitic Quartz Arenite
Muscovite (Mica)
Muscovite - KAl2(AlSi3O10)(OH)2
Petrified Wood
Silicified Wood (SiO2)
Jasper (Iron-stained Quartzite/Chert)
Silicon Dioxide (SiO2) with iron oxide inclusions
Fossilized Crinoid Stem Segment
Crinoid (Phylum Echinodermata, Class Crinoidea)
River Rock (Basalt/Greywacke pebbles)
Fluvial gravel primarily composed of Mafic Volcanic Rock (Basalt) or Lithic Sandstone (Greywacke)
Banded Chert
Microcrystalline Quartz (SiO2)
Yellow Jasper
Silicon Dioxide (SiO2) with high iron inclusion
Jasper (Green variety)
Silicon Dioxide (SiO₂)
Hag Stone (Banded Chert or Limestone with Borehole)
Microcrystalline Quartz (Chert) or Calciferous Siltstone (CaCO3/SiO2)
Gastropod Steinkern (Fossilized Snail Cast)
Phylum Mollusca, Class Gastropoda (Commonly CaCO3 or SiO2 after replacement)
Jasper (specifically Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Petrified Wood
Silicified Wood (primarily SiO2)
Yellow Jasper
Silicon Dioxide (SiO2) with iron inclusions
Brachiopod Fossil (Spiriferid)
Order Spiriferida (Phylum Brachiopoda); mineralized as Calcite (CaCO3) or Chert (SiO2)
Pyrite in Shale
Iron Disulfide (FeS2) in Sedimentary Shale
Petrified Wood
Silicified Wood (SiO2)
Gold Nugget
Native Gold (Au)
Stromatolite
Cyanobacteria fossilized formation (CaCO3)
Orthoceras Fossil in Limestone
Orthoceras regulare
Petrified Wood
Silicified Wood (SiO2)
River Quartz
Quartz (Silicon Dioxide, SiO2)
Chert Nodule
Microcrystalline Silica (SiO2)
Rhodonite
Rhodonite (Manganese Silicate), (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Rhodonite (Mn, Fe, Mg, Ca)SiO3