Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Category
Browse sedimentary (secondary formation) specimens identified by the Rock Identifier community.
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Bituminous Coal
Bituminous coal (Carbonaceous sedimentary rock)
Sandstone
Arenite (primarily SiO2 with various cementing agents)
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily SiO2 with FeO(OH) impurities)
Fluorite
Fluorite (Calcium Fluoride - CaF2)
Agate
Agate (Microcrystalline Quartz, SiO2)
Yellow Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Sandstone (Ferruginous)
Arenite (Iron-rich)
Sandstone (Banded)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (with prominent jointing/fractures)
Arenite (composed primarily of SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Sandstone
Arenite
Prehnite with Epidote inclusions
Prehnite: Ca2Al(AlSi3O10)(OH)2; Epidote: Ca2(Al,Fe)3(SiO4)3(OH)
Chert (with Quartz vein/coating)
Microcrystalline Quartz (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Brecciated Chert
Brecciated Chert (Microcrystalline Quartz, SiO2)
Sandstone
Arenite (primarily SiO2 - Silicon Dioxide)
Sandstone
Arenite (primarily SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone (likely Quartzose Sandstone)
Arenite (SiO2 predominantly)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Yellow Jasper
Silicon Dioxide (SiO2) with Goethite or Iron Oxide inclusions
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)
Pyrite
Iron Pyrite (FeS2)
Septarian Nodule or Mud Crack Fossil
Septarian Nodule (Concretion)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated Iron Oxide)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Chalcedony or Chert/Jasper with secondary mineral staining
SiO2 (for chalcedony/quartz) with possible secondary copper minerals (e.g., CuSiO3·nH2O for chrysocolla, Cu2(CO3)(OH)2 for malachite) or iron oxides/hydroxides.
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Sandstone (Ferruginous)
Arenite (Fe-rich)
Jasper (Zebra Jasper)
Silicon Dioxide (SiO2) with impurities
Chert Pebble with Quartz Veining
Microcrystalline Quartz (SiO2)
Sandstone with Quartz Veining
Clastic sedimentary rock (SiO2 dominated)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Banded Agate (Yellow/Honey Agate)
Agate (Cryptocrystalline Quartz, SiO2)
Carnelian
Carnelian (a variety of Chalcedony, SiO2)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 cement)
Goethite (Iron Ore)
Goethite (FeO(OH))