Rock Identifier

Category

Sedimentary (Cryptocrystalline Silica)

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

Black Onyx (Silicon Dioxide (SiO2)) — mineral

Black Onyx

Silicon Dioxide (SiO2)

Brown Jasper (Likely) (Jasper (Cryptocrystalline Silicon Dioxide - SiO2)) — Mineral

Brown Jasper (Likely)

Jasper (Cryptocrystalline Silicon Dioxide - SiO2)

Carnelian (Carnelian (SiO2 with Iron oxide impurities)) — Mineral (Chalcedony variety)

Carnelian

Carnelian (SiO2 with Iron oxide impurities)

Mineral (Chalcedony variety)

Chert or Flint (polished/water-worn) (Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.) — Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)

Chert or Flint (polished/water-worn)

Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.

Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)

Flint (Chert) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Flint (Chert)

Cryptocrystalline Quartz (SiO2)

Jasper (Tumbled) (Silicon Dioxide (SiO₂)) — sedimentary (cryptocrystalline quartz)

Jasper (Tumbled)

Silicon Dioxide (SiO₂)

sedimentary (cryptocrystalline quartz)

Agate (Agate (Cryptocrystalline Variety of Quartz, SiO2)) — Mineral

Agate

Agate (Cryptocrystalline Variety of Quartz, SiO2)

Agate (or Chalcedony) (SiO2 (Silicon Dioxide) - a cryptocrystalline variety of quartz) — Mineral

Agate (or Chalcedony)

SiO2 (Silicon Dioxide) - a cryptocrystalline variety of quartz

Yellow Agate (Chalcedony (cryptocrystalline silica), SiO2) — mineral

Yellow Agate

Chalcedony (cryptocrystalline silica), SiO2

Jasper (Jasper (a variety of Chalcedony, SiO2)) — Mineral

Jasper

Jasper (a variety of Chalcedony, SiO2)

Onyx (Black Onyx) (Silicon Dioxide (SiO2)) — mineral

Onyx (Black Onyx)

Silicon Dioxide (SiO2)

Carnelian (Carnelian (Microcrystalline Quartz, SiO2)) — mineral

Carnelian

Carnelian (Microcrystalline Quartz, SiO2)

Ocean Jasper (Silicon Dioxide (SiO2) with various inclusions) — igneous/sedimentary mixed (Orbicular Jasper)

Ocean Jasper

Silicon Dioxide (SiO2) with various inclusions

igneous/sedimentary mixed (Orbicular Jasper)

Agate (specifically a Thunderegg/Agate Nodule) (Cryptocrystalline Quartz (SiO2)) — mineral

Agate (specifically a Thunderegg/Agate Nodule)

Cryptocrystalline Quartz (SiO2)

Chert (varietal known as Jasper or Flint) (Silicon Dioxide (SiO2)) — Sedimentary Rock

Chert (varietal known as Jasper or Flint)

Silicon Dioxide (SiO2)

Sedimentary Rock

Jasper with Pyrite (Gold-colored inclusions) (Silicon Dioxide (SiO2) with Iron Disulfide (FeS2) inclusions) — sedimentary (chemical/biological)

Jasper with Pyrite (Gold-colored inclusions)

Silicon Dioxide (SiO2) with Iron Disulfide (FeS2) inclusions

sedimentary (chemical/biological)

Jasper (Silicon Dioxide (SiO2) - a variety of Chalcedony (Cryptocrystalline Quartz)) — Mineral

Jasper

Silicon Dioxide (SiO2) - a variety of Chalcedony (Cryptocrystalline Quartz)

Jasper in Rhyolite matrix (Silicon Dioxide (SiO2) with various inclusions in Felsic Igneous matrix) — igneous

Jasper in Rhyolite matrix

Silicon Dioxide (SiO2) with various inclusions in Felsic Igneous matrix

Ocean Jasper (Silicon Dioxide (SiO2)) — Mineral_variety_of_Chalcedony

Ocean Jasper

Silicon Dioxide (SiO2)

Mineral_variety_of_Chalcedony

Botryoidal Chalcedony with Calcite (Chalcedony (SiO2 with accessory minerals, likely CaCO3)) — Mineral

Botryoidal Chalcedony with Calcite

Chalcedony (SiO2 with accessory minerals, likely CaCO3)

Chalcedony (Chalcedony (a microcrystalline variety of Quartz, SiO2)) — Mineral

Chalcedony

Chalcedony (a microcrystalline variety of Quartz, SiO2)

Red Jasper (River Pebble) (Silicon Dioxide (SiO2) with hematite impurities) — sedimentary (microcrystalline quartz)

Red Jasper (River Pebble)

Silicon Dioxide (SiO2) with hematite impurities

sedimentary (microcrystalline quartz)

Mookaite Jasper (Siliceous sedimentary rock (variety of Jasper/Chert)) — Sedimentary Rock

Mookaite Jasper

Siliceous sedimentary rock (variety of Jasper/Chert)

Sedimentary Rock

Banded Iron Formation (Banded Iron Formation (BIF)) — Sedimentary Rock

Banded Iron Formation

Banded Iron Formation (BIF)

Sedimentary Rock

Turquoise (Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O) — mineral

Turquoise

Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O

Limonite (Ochreous) (FeO(OH)·nH2O (Hydrated Iron Oxide)) — mineral

Limonite (Ochreous)

FeO(OH)·nH2O (Hydrated Iron Oxide)

Dragon Blood Jasper (Epidote with Red Piedmontite (Chalcedony/Quartz variant)) — sedimentary

Dragon Blood Jasper

Epidote with Red Piedmontite (Chalcedony/Quartz variant)

Chert (potentially Flint or Mudstone) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (potentially Flint or Mudstone)

Microcrystalline Quartz (SiO2)

Red Jasper (beads) (SiO₂ (Silicon Dioxide)) — Mineral, variety of chalcedony (microcrystalline quartz)

Red Jasper (beads)

SiO₂ (Silicon Dioxide)

Mineral, variety of chalcedony (microcrystalline quartz)

Thunderegg (Ate Agate/Jasper Geode) (Silicon Dioxide (SiO2) within Rhyolite/Perlite matrix) — sedimentary/igneous intermediary

Thunderegg (Ate Agate/Jasper Geode)

Silicon Dioxide (SiO2) within Rhyolite/Perlite matrix

sedimentary/igneous intermediary

Jasper (likely Lake Superior Jasper) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary (silica-rich mineral variety)

Jasper (likely Lake Superior Jasper)

Silicon Dioxide (SiO2) with iron oxide inclusions

sedimentary (silica-rich mineral variety)

Chert (Jasper/Agate variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Agate variety)

Microcrystalline quartz (SiO2)

Carnelian (Carnelian (SiO2 - Silicon Dioxide with Iron Oxide impurities)) — mineral

Carnelian

Carnelian (SiO2 - Silicon Dioxide with Iron Oxide impurities)

Pink Dyed Agate (Silicon Dioxide (SiO2) with synthetic pigment) — mineral

Pink Dyed Agate

Silicon Dioxide (SiO2) with synthetic pigment

Petrified Wood (Jet or Coalified Wood appearance) (Silicified wood (principally SiO2) or Carbonized Wood) — sedimentary

Petrified Wood (Jet or Coalified Wood appearance)

Silicified wood (principally SiO2) or Carbonized Wood

Carnelian (Carnelian (a variety of Chalcedony, SiO

₂)) — Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)

Carnelian

Carnelian (a variety of Chalcedony, SiO ₂)

Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)

Red Jasper (possibly) (Jasper (a variety of Chalcedony, SiO2)) — Mineral

Red Jasper (possibly)

Jasper (a variety of Chalcedony, SiO2)

Banded Agate (specifically sardonyx or carnelian agate variety) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Agate (specifically sardonyx or carnelian agate variety)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Fossilized Wood (Petrified Wood) (Silicified Wood (primarily quartz/chalcedony replacing organic matter)) — Sedimentary (with some aspects of mineral replacement)

Fossilized Wood (Petrified Wood)

Silicified Wood (primarily quartz/chalcedony replacing organic matter)

Sedimentary (with some aspects of mineral replacement)

Quartz (possibly milky quartz) (Quartz (Silica; SiO₂)) — Mineral

Quartz (possibly milky quartz)

Quartz (Silica; SiO₂)

Botryoidal Chalcedony (Chalcedony (SiO2)) — Mineral

Botryoidal Chalcedony

Chalcedony (SiO2)

Geode with Quartz and possibly Jasper/Hematite (Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides) — Mineral/Sedimentary Geode

Geode with Quartz and possibly Jasper/Hematite

Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides

Mineral/Sedimentary Geode