Gneiss
High-grade regional metamorphic rock (Foliated)
metamorphic
Category
Sedimentary (Jasper), Mineral (Aquamarine)
Browse sedimentary (jasper), mineral (aquamarine) specimens identified by the Rock Identifier community.
Quartz / Limestone Gravel
SiO2 (Silicon Dioxide) and CaCO3 (Calcium Carbonate)
igneous and sedimentary mixture
Limestone with Calcite Veins
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
mineral
Sandstone (Quartzose Sandstone)
Clastic Terrigenous Sedimentary Rock (primarily SiO2)
sedimentary
Quartz Vein in Siltstone
SiO2 (Quartz) on clastic sedimentary matrix
sedimentary
Sandstone (Pebble)
Arenite (composed primarily of SiO2)
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily Quartz - SiO2)
sedimentary
Dendritic Siltstone (or Mudstone)
Siltstone with Manganese Oxide dendrites
sedimentary
Magnetite / Hematite mix (Iron Ore)
Fe3O4 (Magnetite) / Fe2O3 (Hematite)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Sandstone (likely Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Gneiss (specifically Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Biotite/Amphibole)
metamorphic
Sandstone (with manganese staining)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Geode (unopened)
SiO2 - Chert-shelled concretion (mostly Quartz)
sedimentary
Feldspar
KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8
mineral
Sandstone (Ferruginous)
Arenite with Iron Oxides
sedimentary
Gneiss (specifically a Granitic Gneiss specimen)
Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)
metamorphic
Sandstone (Quartzite-rich Pebble)
Arenite (primarily SiO2)
sedimentary
Red Sandstone
Arenite (primarily Quartz, SiO2, with Iron Oxide cementing agent)
sedimentary
Quartz Crystal with Inclusions
Silicon Dioxide (SiO2)
mineral
Ironstone Concretion (Limonite/Hematite Nodules)
Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)
sedimentary
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)
sedimentary
Hematite
Iron(III) oxide (Fe2O3)
mineral
Sandstone (Gneissic or Banded)
Clastic Sedimentary Rock (composed predominantly of SiO2)
sedimentary
Breccia
Breccia - Clastic sedimentary rock
sedimentary
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Sulfur (with possible Cullet Glass or Slag imitation)
Native Sulfur (S8)
mineral
Quartz (Milky or Common Quartz)
Silicon Dioxide (SiO2)
mineral
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
mineral
Gneiss (with Quartz-Feldspar vein)
Gneiss (high-grade metamorphic rock) containing Quartz (SiO2) and Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8)
metamorphic
Quartz / Quartz Geode fragment
Silicon Dioxide (SiO2)
mineral
Carnelian Agate
Chalcedony (SiO2 with Iron Oxide impurities)
mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Sandstone (Ferruginous)
Arenite with Iron-oxide inclusions (SiO2 primarily)
sedimentary
Biotite (Mica)
Biotite group (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Sandstone (with potential Arkose/Lithic characteristics)
Arenite (Sedimentary rock composed of sand-sized grains)
sedimentary
Sandstone
Arenite (predominantly Quartz Sandstone)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone
Arenite
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary