Clay (as a rock-forming material)
Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)
Category
Browse sedimentary (formed from silica deposits) specimens identified by the Rock Identifier community.
Clay (as a rock-forming material)
Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)
Chert (and Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Yellow Jasper
Silicon Dioxide with Iron inclusions (SiO2)
Quartzite (Sugar Quartz)
Quartzite (primarily SiO2)
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
Quartzite
Quartzite (primarily SiO2)
Grey and White Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Pink Chalcedony (Agate/Jasper blend)
Silicon Dioxide (SiO₂)
Chert (Jasper)
Microcrystalline Silica (SiO2)
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Banded Iron Formation
Banded Iron Formation (BIF)
Blue Chalcedony
Silicon Dioxide (SiO2)
Carnelian
Carnelian (SiO2 variant)
Chert
Chert (Silicon Dioxide, SiO2)
Pebble or Cobble (likely composed of sandstone or conglomerate)
Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)
Chert (varietal Flint)
Silicon Dioxide (SiO2)
Yellow Chalcedony (common opal or chert variant)
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Chert (often called Flint when dark)
Sedimentary cryptocrystalline quartz (SiO2)
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Chert (variant Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (and Flint)
Silicon Dioxide (SiO2)
Heliotrope (Bloodstone)
Cryptocrystalline Quartz (SiO2) with inclusions of Hematite (Fe2O3)
Jasper
Silicon dioxide (SiO2)
Jasper with Quartz
Silicon Dioxide (SiO2) - Chalcedony variety
Quartz (Common or Milky Quartz)
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Agate (Carnelian-like)
Chalcedony (Silicon Dioxide, SiO2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (Flint)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Red Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Gneiss with Quartz Veining
Gneiss (High-grade regional metamorphic rock)
Yellow Jasper / Chert
Jasper (Silica/Quartz) - SiO2
Quartz Pebble
Silicon Dioxide (SiO2)
Carnelian
Carnelian (Silicon Dioxide - SiO2)
Chert Pebble (Flint)
Microcrystalline/Cryptocrystalline Quartz (SiO2)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint variety)
Chert (SiO2)
Limonite
Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)