Rock Identifier

Category

Sedimentary Rock (Technically A Variety Of Chalcedony)

Browse sedimentary rock (technically a variety of chalcedony) specimens identified by the Rock Identifier community.

Chert / Chalcedony (Silicon Dioxide (SiO2)) — sedimentary

Chert / Chalcedony

Silicon Dioxide (SiO2)

Blue Chalcedony (Cryptocrystalline Quartz (SiO2)) — mineral

Blue Chalcedony

Cryptocrystalline Quartz (SiO2)

Breccia (Clastic Breccia (General mineral composition depends on fragments, often SiO2 or CaCO3)) — sedimentary

Breccia

Clastic Breccia (General mineral composition depends on fragments, often SiO2 or CaCO3)

Chalcedony (Agate/Blue Quartzite) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Agate/Blue Quartzite)

Silicon Dioxide (SiO2)

K2 Jasper (Beads) (Granodiorite with Azurite and Malachite) — igneous

K2 Jasper (Beads)

Granodiorite with Azurite and Malachite

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

Chalcedony (Botryoidal Agate)

Silicon Dioxide (SiO2)

Carnelian Agate (Chalcedony (SiO2 with iron oxide impurities)) — mineral

Carnelian Agate

Chalcedony (SiO2 with iron oxide impurities)

Milky Quartz (Quartz Vein) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (Quartz Vein)

Silicon Dioxide (SiO2)

Shale or Argillite (Shale (sedimentary) / Argillite (metamorphic)) — Sedimentary or Metamorphic (low-grade)

Shale or Argillite

Shale (sedimentary) / Argillite (metamorphic)

Sedimentary or Metamorphic (low-grade)

White Quartz (Quartz (SiO2)) — Mineral

White Quartz

Quartz (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Grey Chalcedony (Agate)

Silicon Dioxide (SiO2)

River Cobble (likely Sandstone or Siltstone type) (Sandstone or Siltstone (common rock types that form river cobbles)) — Sedimentary Rock (specifically a clastic sedimentary rock formed into a cobble)

River Cobble (likely Sandstone or Siltstone type)

Sandstone or Siltstone (common rock types that form river cobbles)

Sedimentary Rock (specifically a clastic sedimentary rock formed into a cobble)

Quartz (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz

Quartz (SiO2 - Silicon Dioxide)

Iceland Spar (Optical Calcite) (Calcite (Calcium Carbonate, CaCO3)) — mineral

Iceland Spar (Optical Calcite)

Calcite (Calcium Carbonate, CaCO3)

Chert (varietal Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (varietal Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sandstone (Pebble/Cobble) (Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)) — Sedimentary

Sandstone (Pebble/Cobble)

Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)

Chalcedony (Botryoidal/Tumbled Agate) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Botryoidal/Tumbled Agate)

Silicon Dioxide (SiO2)

Chert (and Flint variant) (Chert (SiO2)) — sedimentary

Chert (and Flint variant)

Chert (SiO2)

Red Sandstone (Arenite (primarily Quartz with Hematite cement)) — sedimentary

Red Sandstone

Arenite (primarily Quartz with Hematite cement)

Blue Lace Agate (Tumbled) (Silicon Dioxide (SiO2)) — mineral

Blue Lace Agate (Tumbled)

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz) (Silicon Dioxide (SiO2) with iron inclusions) — mineral

Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz)

Silicon Dioxide (SiO2) with iron inclusions

Ocean Jasper (Spherulitic Chalcedony (SiO2)) — sedimentary

Ocean Jasper

Spherulitic Chalcedony (SiO2)

Agate (River Pea) (Microcrystalline Chalcedony (SiO2)) — sedimentary

Agate (River Pea)

Microcrystalline Chalcedony (SiO2)

Serpentine (Serpentinite) (Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4) — metamorphic

Serpentine (Serpentinite)

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Tree Agate (Silicon Dioxide (SiO2) with Dendritic Inclusions) — Mineral

Tree Agate

Silicon Dioxide (SiO2) with Dendritic Inclusions

Quartz (Silicon Dioxide (SiO₂)) — Mineral

Quartz

Silicon Dioxide (SiO₂)

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

Sandstone (Painted)

Arenite (primarily SiO2)

Pyrite (Iron Disulfide (FeS2)) — Mineral

Pyrite

Iron Disulfide (FeS2)

Chalcedony (specifically Common Opal or Agate variant) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (specifically Common Opal or Agate variant)

Silicon Dioxide (SiO2)

Agate (or Banded Agate) (Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)) — Mineral, specifically a Cryptocrystalline Quartz variety

Agate (or Banded Agate)

Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)

Mineral, specifically a Cryptocrystalline Quartz variety

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Quartz (Milky Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Carnelian (Chalcedony) (Silicon Dioxide (SiO2) with trace Iron Oxide) — mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2) with trace Iron Oxide

Yellow Chalcedony (Agate/Jasper mix) (Silicon Dioxide (SiO2)) — mineral

Yellow Chalcedony (Agate/Jasper mix)

Silicon Dioxide (SiO2)

Sandstone with Quarzite clasts (Arenite (SiO2 based)) — sedimentary

Sandstone with Quarzite clasts

Arenite (SiO2 based)

Dragon Vein Agate (Silicon Dioxide (SiO2)) — mineral

Dragon Vein Agate

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Epidote (Epidote (formula: Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))) — mineral

Epidote

Epidote (formula: Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Agatized Fossil or Chalcedony Nodule (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Agatized Fossil or Chalcedony Nodule

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz