Gneiss (Banded Gneiss)
Gneiss
Category
Browse sedimentary (alluvial deposit) specimens identified by the Rock Identifier community.
Gneiss (Banded Gneiss)
Gneiss
Clear Quartz
Silicon Dioxide (SiO2)
Calcite
Calcium Carbonate (CaCO3)
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Iron-stained Quartz (with Limonite/Hematite)
Silicon Dioxide (SiO2) with Iron Oxide inclusions (FeO(OH) or Fe2O3)
Crushed Limestone
Calcium Carbonate (CaCO3)
Chert (Cherty Limestone or Flint)
Microcrystalline Silica (SiO2)
River Pebble (Quartz-rich)
Silicon Dioxide (SiO2) with various inclusions
Jasper
Jasper (Silicon Dioxide, SiO2)
Chert (Common Chert)
Cryptocrystalline Quartz (SiO2)
Red Sandstone
Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)
Petrified Wood
Silicified Wood (SiO2)
Chert (Black Chert/Flint)
Cryptocrystalline Quartz (SiO2)
Sandstone (Micaceous)
Arenite (primarily SiO2 with Phyllosilicates)
Shale or Siltstone
Sedimentary Rock (Siliciclastic)
Siltstone or Mudstone
Argillaceous sedimentary rock
Chert (or Flint)
SiO2 (predominantly microcrystalline quartz)
Sandstone
Arenite (composed primarily of SiO2)
Quartz Vein in Siltstone
SiO2 (Quartz) on clastic sedimentary matrix
Sandstone (with Iron Siderite Concretion)
Arenite with Ironstone Concretion (FeCO3)
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
Jasper (with Manganese or Iron inclusions)
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
Breccia
Clastic Breccia (General mineral composition depends on fragments, often SiO2 or CaCO3)
Red Chert (Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Sandstone (Red)
Arenite (SiO2 with Fe2O3)
Chert (Siliceous Mudstone variant)
Microcrystalline quartz (SiO2)
Sandstone (likely Arkosic or Quartzose)
Sandstone (SiO2 dominated)
Chert (often called Flint or Jasper when red)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Sandstone
Arenite (primarily SiO2)
Sandstone (Quartzose Sandstone)
Arenite (SiO2 primarily)
Chert (Banded)
Microcrystalline Quartz (SiO2)
Chert (Pink Jasper)
Microcrystalline Quartz (SiO2)
Blue Lace Agate
Agate (Variety of Chalcedony, SiO2)
Chert (Yellow or Brown Jasper)
Microcrystalline Quartz (SiO2)
Bauxite
Al2O3·2H2O (principally composed of gibbsite, boehmite, and diaspore)
Sandstone
Arenite (composed primarily of Quartz, SiO2)
Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Clear Quartz
Crystalline Silicon Dioxide (SiO2)
Calcite
Calcium Carbonate (CaCO3)
Breciated Chert
Brecciated Chert (Microcrystalline Quartz, SiO2)