Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Category
Browse rock (likely sedimentary) specimens identified by the Rock Identifier community.
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Quartzite
Quartzite (primarily SiO2)
Gneiss (Banded Gneiss)
Gneiss
Yellow Chert (Gold-toned Jasper)
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Chert / Jasper
Microcrystalline Quartz (SiO2)
Chert (Brecciated River Cobble)
Silicon Dioxide (SiO2)
Chert (Jasper/Ironstone variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Carnelian (Red Chalcedony)
Silicon Dioxide (SiO2)
Limonite (Iron Ore/Sandstone mixture)
Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix
Quartzite River Rock (with Limonite staining)
Quartzite (SiO2)
Pyrite (on host rock/ore)
Iron Sulfide (FeS2)
Ironstone Concretion (Moqui Marble Type)
Goethite/Hematite-cemented Sandstone Concretion
Laterite
Laterite (no specific mineral formula as it's a rock type)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Jasper and Chert Conglomerate
Ferruginous Microcrystalline Quartz (SiO2)
Breccia
Clastic Breccia (General mineral composition depends on fragments, often SiO2 or CaCO3)
Red Sandstone
Arenite (Fe2O3-rich)
Sandstone with Liesegang Rings
Arenite with secondary Iron oxide (Limonite/Goethite) precipitation
Greywacke (River Slikenside)
Greywacke (Lithic Sandstone)
Fossil Coral
Fossilized Scleractinia or Tabulata (various genera/species)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Jasper (Red/Brown Variety)
Jasper (Silicon Dioxide, SiO2 plus Iron Oxide impurities)
Red Sandstone (Old Red Sandstone)
Ferruginous Sandstone (SiO2 + Fe2O3)
Jasper
Silicon dioxide (SiO2) with iron impurities
Banded Gneiss
Gneiss (Metamorphic high-grade, predominantly SiO2, Al2O3, K2O, Na2O)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Clear Quartz (or Rock Crystal)
Quartz (SiO₂ - Silicon Dioxide)
Agate and Amethyst (Quartz variants)
Silicon Dioxide (SiO2) - Microcrystalline Quartz and Crystalline Quartz
Quartz Geode (with Agate banding)
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Milky Quartz
Silicon Dioxide (SiO2)
Banded Iron Formation (BIF)
Banded Iron Formation
Gneiss
Gneiss (Metamorphic rock composed primarily of quartz, feldspar, and mica)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Dendritic Siltstone (or Mudstone)
Siltstone with Manganese Oxide dendrites
Brachiopod Fossil (Spiriferid)
Order Spiriferida (Phylum Brachiopoda); mineralized as Calcite (CaCO3) or Chert (SiO2)
Chert (Arrowhead variety)
Chert (SiO2)
Bumble Bee Jasper
Calcite-bearing Volcanic Tuff (not a true Jasper)
Greywacke with Quartz Veins
Lithic Sandstone (Greywacke) with SiO2 inclusions