Shale
Shale (composition varies: primarily clay minerals and quartz)
Category
Browse man made composite (lithified equivalent of sedimentary) specimens identified by the Rock Identifier community.
Shale
Shale (composition varies: primarily clay minerals and quartz)
Sandstone
Arenite (composed primarily of SiO2)
Rhodochrosite
Manganese Carbonate (MnCO3)
Quartz Pebble
Silicon dioxide (SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Graphite-rich schist (likely graphite ore)
Graphite-bearing schist; predominantly graphitic carbon (C) with mica, quartz, and possible feldspar
Polished hematite-rich ironstone
Hematite (Fe₂O₃), likely mixed with magnetite and iron-rich jasper
Decorative polished pebbles
Likely mixed quartz-rich lithologies, including quartzite, jasper, and/or basalt
Iron-rich chert or jasper pebble
Microcrystalline quartz (SiO₂), colored by iron oxides
Unidentified weathered rock fragments
Likely mixed silicate rocks; specific identification requires testing
Psilomelane (Black Hematite varietal)
Barium Manganese Oxide (Ba,H2O)2Mn5O10
Pink Thulite
Thulite (Ca2Al3(SiO4)3(OH)) - Pink Zoisite
Rhodonite
Manganese Inosilicate (Mn,Fe,Mg,Ca)SiO3
Sandstone
Arenite (SiO2 primarily)
Hematite
Iron(III) oxide (Fe2O3)
Red Sandstone
Arenite (primarily quartz with iron oxide cement)
Sandstone
Quartz arenite / Lithic sandstone
Pyrite
Iron Sulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Graphite
Graphite (C)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Rhodochrosite
Rhodochrosite, Manganese Carbonate (MnCO3)
Quartz (Agate/Chalcedony variety)
Silicon Dioxide (SiO2)
Magnetite (Iron Ore)
Magnetite (Fe3O4)
Rhodochrosite
Manganese Carbonate (MnCO3)
White Quartz
Silicon Dioxide (SiO2)
Jasper
Microcrystalline Quartz (SiO2) with impurities
Zebra Jasper
Banded microcrystalline quartz (SiO2)
Chalcedony
Silicon Dioxide (SiO2)
Green Jasper
Silicon Dioxide (SiO2) with impurities
Red Jasper
Jasper (Silicon Dioxide) - SiO2
Potassium Feldspar
Orthoclase (KAlSi3O8)
Pyrite in Matrix (Fool's Gold)
Iron Disulfide (FeS2)
Calcite
Calcium Carbonate (CaCO3)
Pyrite
Iron Sulfide (FeS2)
Potassium Feldspar
K-Feldspar (Orthoclase/Microcline) KAlSi3O8
Hematite
Iron(III) oxide (Fe2O3)
Quartz Pebble
Silicon Dioxide (SiO2)
Sandstone (likely Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2)
Fossiliferous Limestone
Calcium Carbonate (CaCO3) matrix with biogenic fragments
Sandstone
Arenite (SiO2 primarily)
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)