Rock Identifier

Category

Sedimentary (Cryptocrystalline Silica)

Browse sedimentary (cryptocrystalline silica) specimens identified by the Rock Identifier community.

Agate (Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Agate (Chalcedony)

Silicon Dioxide (SiO2)

Indian Agate (Cryptocrystalline Quartz (SiO2)) — mineral

Indian Agate

Cryptocrystalline Quartz (SiO2)

Banded Agate (specifically Moss or River Agate variety) (Cryptocrystalline Quartz (SiO2)) — mineral

Banded Agate (specifically Moss or River Agate variety)

Cryptocrystalline Quartz (SiO2)

Banded Agate (Cryptocrystalline Quartz (SiO2)) — mineral

Banded Agate

Cryptocrystalline Quartz (SiO2)

Banded Agate (specifically Carnelian Agate) (Cryptocrystalline Quartz (SiO2)) — mineral

Banded Agate (specifically Carnelian Agate)

Cryptocrystalline Quartz (SiO2)

Banded Agate (specifically Sardonyx or Black Agate variety) (Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz) — mineral

Banded Agate (specifically Sardonyx or Black Agate variety)

Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz

Chert (Flint variety) (Chert (SiO2)) — sedimentary

Chert (Flint variety)

Chert (SiO2)

Chert (Flint variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint variety)

Silicon Dioxide (SiO2)

Chert (Flint) (Silicon Dioxide (SiO2)) — Sedimentary

Chert (Flint)

Silicon Dioxide (SiO2)

Polished Chert (Flint) (Silicon Dioxide (SiO2)) — sedimentary

Polished Chert (Flint)

Silicon Dioxide (SiO2)

Jasper (likely Kambaba or Crocodile Jasper variety) (Silicon Dioxide (SiO2) with inclusions) — sedimentary

Jasper (likely Kambaba or Crocodile Jasper variety)

Silicon Dioxide (SiO2) with inclusions

Limonite (Iron Ore) (Hydrous ferric oxides (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Hydrous ferric oxides (FeO(OH)·nH2O)

Banded Calcite (often sold as 'Mexican Onyx') (Calcite (Calcium Carbonate - CaCO3)) — sedimentary

Banded Calcite (often sold as 'Mexican Onyx')

Calcite (Calcium Carbonate - CaCO3)

Turritella Agate (Fossiliferous Chert) (Silicified Elimia tenera (Fossiliferous Chalcedony)) — sedimentary

Turritella Agate (Fossiliferous Chert)

Silicified Elimia tenera (Fossiliferous Chalcedony)

Red Jasper (Jasper (a variety of Quartz, SiO2)) — Mineral

Red Jasper

Jasper (a variety of Quartz, SiO2)

Banded Agate (Onyx type) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Agate (Onyx type)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Banded Agate (specifically shades of Carnelian Agate) (Silicon Dioxide (SiO2)) — mineral

Banded Agate (specifically shades of Carnelian Agate)

Silicon Dioxide (SiO2)

Banded Agate (Cryptocrystalline Quartz (SiO2)) — mineral

Banded Agate

Cryptocrystalline Quartz (SiO2)

Black Onyx (Cryptocrystalline Quartz (SiO2)) — mineral

Black Onyx

Cryptocrystalline Quartz (SiO2)

Black Onyx (Silicon Dioxide (SiO2)) — mineral

Black Onyx

Silicon Dioxide (SiO2)

Quartz Geode (partially formed/chalcedony with iron staining) (Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides) — Mineral/Sedimentary Rock Feature

Quartz Geode (partially formed/chalcedony with iron staining)

Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides

Mineral/Sedimentary Rock Feature

Black Onyx (Silicon dioxide (SiO2)) — mineral

Black Onyx

Silicon dioxide (SiO2)

Banded Agate (specifically Mexican Lace Agate variety appearance) (Silicon Dioxide (SiO2 / Chalcedony)) — mineral

Banded Agate (specifically Mexican Lace Agate variety appearance)

Silicon Dioxide (SiO2 / Chalcedony)

Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Chert (variations include Flint/Jasper) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (variations include Flint/Jasper)

Chert (Silicon Dioxide, SiO2)

Banded Agate (Carnelian type) (Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony) — mineral

Banded Agate (Carnelian type)

Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Banded Chalcedony (Agate) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Chalcedony (Agate)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Turquoise (set in silver jewelry) (Turquoise - CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)) — mineral

Turquoise (set in silver jewelry)

Turquoise - CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)

Greenstone (Greywacke or Nephrite Jade variant) (Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)) — metamorphic

Greenstone (Greywacke or Nephrite Jade variant)

Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)

Red Jasper (River Siltstone) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Red Jasper (River Siltstone)

Silicon Dioxide (SiO2) with iron oxide inclusions

Banded Agate (Onyx Variety) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Agate (Onyx Variety)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

White Agate (Tumbled) (Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony) — mineral

White Agate (Tumbled)

Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony

Banded Agate (specifically Sardonyx or Carnelian Agate) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Agate (specifically Sardonyx or Carnelian Agate)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Agate (Geode nodule) (Cryptocrystalline Quartz (SiO2)) — mineral

Agate (Geode nodule)

Cryptocrystalline Quartz (SiO2)

Shale or Mudstone (Based on appearance) (Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)) — Sedimentary

Shale or Mudstone (Based on appearance)

Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)

Petrified Wood (Silicified wood, primarily composed of Quartz (SiO2)) — Mineral, often found in sedimentary deposits

Petrified Wood

Silicified wood, primarily composed of Quartz (SiO2)

Mineral, often found in sedimentary deposits

Carnelian Agate (Carnelian (Silicon Dioxide - SiO2)) — mineral

Carnelian Agate

Carnelian (Silicon Dioxide - SiO2)

Agate (Cryptocrystalline Quartz (SiO2)) — mineral

Agate

Cryptocrystalline Quartz (SiO2)

Banded Agate (specifically Red Agate or Sardonyx variety) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Agate (specifically Red Agate or Sardonyx variety)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Dyed Purple Agate (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Dyed Purple Agate

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Agate (Moss or Lake Superior type) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Agate (Moss or Lake Superior type)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz