Rock Identifier

Category

Sedimentary (Cryptocrystalline Silica)

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

Chert (with possible fossils) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (with possible fossils)

Microcrystalline quartz (SiO2)

Green Jasper (Silicon Dioxide (SiO2)) — sedimentary

Green Jasper

Silicon Dioxide (SiO2)

Banded Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Banded Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Yellow Jasper (Chalcedony (Silicon Dioxide with Iron inclusions), SiO2) — sedimentary

Yellow Jasper

Chalcedony (Silicon Dioxide with Iron inclusions), SiO2

Jasper (Brown Iron-Rich Variety) (Silicon Dioxide (SiO2) with Fe2O3 (Iron Oxide/Crystalline Quartz)) — sedimentary

Jasper (Brown Iron-Rich Variety)

Silicon Dioxide (SiO2) with Fe2O3 (Iron Oxide/Crystalline Quartz)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Yellow Jasper (Chalcedony (Silicon Dioxide with iron inclusions), SiO2) — sedimentary

Yellow Jasper

Chalcedony (Silicon Dioxide with iron inclusions), SiO2

Red Jasper (Microcrystalline Quartz (SiO2) with Hematite impurities) — sedimentary

Red Jasper

Microcrystalline Quartz (SiO2) with Hematite impurities

Red Jasper (Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions

Red Jasper (possibly Wonderstone) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Red Jasper (possibly Wonderstone)

Silicon Dioxide (SiO2) with iron oxide inclusions

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

Red Jasper (Tumbled)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (Septarian Nodules / Weathered Silex) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Septarian Nodules / Weathered Silex)

Microcrystalline Quartz (SiO2)

Red Jasper (possibly Brecciated Jasper or Bloodstone variety) (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Red Jasper (possibly Brecciated Jasper or Bloodstone variety)

Jasper (Silicon Dioxide, SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Yellow Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Jasper (likely river-worn) (Silicon Dioxide (SiO2)) — sedimentary

Jasper (likely river-worn)

Silicon Dioxide (SiO2)

Jasper (Red Jasper) (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Jasper (Red Jasper)

Silicon Dioxide (SiO2) with Hematite inclusions

Sandstone (Quartzose Sandstone) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartzose Sandstone)

Arenite (primarily SiO2)

Sandstone concretion (Ironstone-stained) (Arenite with Limonite/Hematite staining (Silica-based with Iron Oxides)) — sedimentary

Sandstone concretion (Ironstone-stained)

Arenite with Limonite/Hematite staining (Silica-based with Iron Oxides)

Sandstone (Calcareous or Ferruginous) (Clastic sedimentary rock (SiO2 with CaCO3 or Fe2O3 cement)) — sedimentary

Sandstone (Calcareous or Ferruginous)

Clastic sedimentary rock (SiO2 with CaCO3 or Fe2O3 cement)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Ocean Jasper (Orbicular Jasper (Silicon Dioxide SiO2)) — sedimentary

Ocean Jasper

Orbicular Jasper (Silicon Dioxide SiO2)

Quartzite Pebble (River Rock) (Quartzite (mainly SiO2)) — metamorphic

Quartzite Pebble (River Rock)

Quartzite (mainly SiO2)

Sandstone (likely Quartzose Sandstone) (Arenite) — sedimentary

Sandstone (likely Quartzose Sandstone)

Arenite

Quartz Geode in Sedimentary Matrix (Silicon Dioxide (SiO2) within a limestone/dolostone host) — mineral

Quartz Geode in Sedimentary Matrix

Silicon Dioxide (SiO2) within a limestone/dolostone host

Sandstone (Quartzose) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartzose)

Arenite (primarily SiO2)

Quartz Geode Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Opal (Hydrous silicon dioxide (SiO2·nH2O)) — mineral

Opal

Hydrous silicon dioxide (SiO2·nH2O)

Quartz-veined Schist (or Metasandstone) (Metamorphic Rock with Quartz Veining (SiO2)) — metamorphic

Quartz-veined Schist (or Metasandstone)

Metamorphic Rock with Quartz Veining (SiO2)

Sandstone Cobble (Arenite (Secondary classification based on grain size)) — sedimentary

Sandstone Cobble

Arenite (Secondary classification based on grain size)

Sandstone (Ferruginous) (Arenite with Iron Oxide matrix) — sedimentary

Sandstone (Ferruginous)

Arenite with Iron Oxide matrix

Sandstone (Ferruginous) (Arenite (with Hematite/Limonite cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (with Hematite/Limonite cement)

Sandstone (with Lichen) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (with Lichen)

Arenite (composed primarily of SiO2)

Sandstone (Ferruginous) (Arenite (SiO2 with Fe2O3 inclusions)) — sedimentary

Sandstone (Ferruginous)

Arenite (SiO2 with Fe2O3 inclusions)

Chert (Chert (microcrystalline quartz)) — Sedimentary

Chert

Chert (microcrystalline quartz)

Red Jasper (Silicon Dioxide (SiO2) with Iron Oxide inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Quartz Geode (Quartz (Silicon Dioxide - SiO2) within a Chalcedony and Limonite shell) — sedimentary

Quartz Geode

Quartz (Silicon Dioxide - SiO2) within a Chalcedony and Limonite shell

Sandstone, Quartzite, and River Pebbles (Silicon Dioxide (SiO2) based Sedimentary/Metamorphic structures) — Sedimentary and Metamorphic

Sandstone, Quartzite, and River Pebbles

Silicon Dioxide (SiO2) based Sedimentary/Metamorphic structures

Sedimentary and Metamorphic

Jasper (Wonderstone/Banded Jasper) (Silicon Dioxide (SiO2) with iron oxide impurities) — sedimentary (chemical/biological origin) or volcanic-related metamorphic

Jasper (Wonderstone/Banded Jasper)

Silicon Dioxide (SiO2) with iron oxide impurities

sedimentary (chemical/biological origin) or volcanic-related metamorphic

Chalcedony (Agate) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — mineral

Chalcedony (Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Milky Quartz / Rose Quartz fragment (Silicon Dioxide (SiO2)) — mineral

Milky Quartz / Rose Quartz fragment

Silicon Dioxide (SiO2)

Sandstone (Weathered Pebble) (Arenite (SiO2 primarily)) — sedimentary

Sandstone (Weathered Pebble)

Arenite (SiO2 primarily)