Sandstone
Arenite (often composed of Quartz, SiO2)
Category
Browse sedimentary rock (technically chert, a microcrystalline quartz) specimens identified by the Rock Identifier community.
Sandstone
Arenite (often composed of Quartz, SiO2)
River Pebble (Likely Quartzite or Chert)
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2) with iron oxide impurities
Conglomerate
Clastic sedimentary rock (Psephite)
Red Chert (Jasper)
Silicon Dioxide (SiO2)
Green Chert (Jasper)
Silicon Dioxide (SiO2)
Zebra Jasper (Zebra Stone)
Tumbled Silicon Dioxide (SiO2) with impurities
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Jasper
Silicon Dioxide (SiO2)
Red Quartzite Cobble
Quartzite (primarily SiO2)
Dendritic Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Banded River Cobble with Mafic Dike
Hydrothermally altered Graywacke or Sandstone with Mafic Intrusion
Shale
Shale (composition varies: primarily clay minerals and quartz)
Quartzite with Sandstone/Iron staining
Metamorphic Quartzite (SiO2)
Puddingstone (specifically Gowganda Tillite or St. Joseph Island Puddingstone)
Jasper Conglomerate
Sandstone
Sandstone (clastic sedimentary rock, predominantly SiO2)
Ferruginous Sandstone
Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)
Sandstone
Arenite (composed primarily of SiO2)
Banded Agate
Cryptocrystalline Quartz (SiO2)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (mostly SiO2)
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Red Jasper
Microcrystalline quartz (SiO2) with Hematite (Fe2O3) impurities
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Sandstone (likely Quartzose Sandstone)
Arenite (SiO2 principal composition)
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)
Chert (and associated river cobbles)
Silicon dioxide (SiO2)
Tree Agate (or Moss Agate), faceted into a crystal tower
Dendritic Agate (Silicon Dioxide, SiO2)
Quartzite
Quartzite (primarily SiO2)
Ocean Jasper
Orbicular Jasper (SiO2)
Ferruginous Quartz (Carnelian-tinted Quartz)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Shale
Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)
Jasper (Red/Brown Variety)
Jasper (Microcrystalline Quartz, SiO2)
Herkimer Diamond (Quartz)
Silicon Dioxide (SiO2)
Quartzite River Stone
Quartzite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (Lithic arenite / Quartz arenite)
Sandstone (Weathered Pebble)
Arenite (SiO2 primarily)
Quartz Geode
Silicon Dioxide (SiO2)
Red Sandstone
Arenite (primarily Quartz with Iron Oxide)