Rock Identifier

Category

Rock (Likely Sedimentary)

Browse rock (likely sedimentary) specimens identified by the Rock Identifier community.

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

Quartzite Pebble (River Rock)

Quartzite (mainly SiO2)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Jasper in Quartz (River Cobble) (Silicon Dioxide (SiO2) with Ferric Iron inclusions) — sedimentary

Jasper in Quartz (River Cobble)

Silicon Dioxide (SiO2) with Ferric Iron inclusions

Limestone (Weathered) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Weathered)

Calcium Carbonate (CaCO3)

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

White Agate (Chalcedony)

Silicon Dioxide (SiO2)

Agate (specifically, multi-colored or pastel-dyed agate) (Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).) — Mineral

Agate (specifically, multi-colored or pastel-dyed agate)

Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).

Gneiss (River Cobble) (Gneiss (Foliated Metamorphic Rock)) — metamorphic

Gneiss (River Cobble)

Gneiss (Foliated Metamorphic Rock)

Sandstone (Red Arkose) (Sandstone (Arkose variant, primarily SiO2 with KAlSi3O8)) — sedimentary

Sandstone (Red Arkose)

Sandstone (Arkose variant, primarily SiO2 with KAlSi3O8)

Biotite Mica (K(Mg,Fe)3AlSi3O10(OH)2) — Mineral in a matrix (likely quartz or feldspar)

Biotite Mica

K(Mg,Fe)3AlSi3O10(OH)2

Mineral in a matrix (likely quartz or feldspar)

Chert (White-Tan variety) (Silicon dioxide (SiO2) / Microcrystalline Quartz) — sedimentary

Chert (White-Tan variety)

Silicon dioxide (SiO2) / Microcrystalline Quartz

Puddingstone (Conglomerate) — Sedimentary

Puddingstone

Conglomerate

Laterite (Laterite (Iron/Aluminum-rich oxide)) — sedimentary

Laterite

Laterite (Iron/Aluminum-rich oxide)

Sedimentary Sandstone (Sandstone Slab) (Arenite (SiO2 with Fe2O3 staining)) — sedimentary

Sedimentary Sandstone (Sandstone Slab)

Arenite (SiO2 with Fe2O3 staining)

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

Sandstone (Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Jasper (specifically Bloodstone or Heliotrope variety) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary (chemically precipitated)

Jasper (specifically Bloodstone or Heliotrope variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

sedimentary (chemically precipitated)

Chalcedony in Host Rock (Silicon Dioxide (SiO2)) — mineral

Chalcedony in Host Rock

Silicon Dioxide (SiO2)

Quartz Geode (Crystalline Silicon Dioxide (SiO2) in Geode form) — sedimentary

Quartz Geode

Crystalline Silicon Dioxide (SiO2) in Geode form

Red Jasper (Chalcedony (SiO2 with iron oxide impurities)) — sedimentary

Red Jasper

Chalcedony (SiO2 with iron oxide impurities)

Chert (often called Flint when dark) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Yellow Jasper (Silicon Dioxide (SiO2) with Goethite/Iron oxide inclusions) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with Goethite/Iron oxide inclusions

Gneiss (Gneiss (High-grade regional metamorphic rock)) — metamorphic

Gneiss

Gneiss (High-grade regional metamorphic rock)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Quartz (Common Milky Quartz)

Silicon Dioxide (SiO2)

Concrete (Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)) — sedimentary (anthropogenic / man-made)

Concrete

Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)

sedimentary (anthropogenic / man-made)

Anthracite Coal (Anthracite (Carbon-rich Sedimentary-to-Metamorphic Rock)) — metamorphic

Anthracite Coal

Anthracite (Carbon-rich Sedimentary-to-Metamorphic Rock)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Zebra Jasper (Silicon dioxide (SiO2) with various impurities) — Sedimentary

Zebra Jasper

Silicon dioxide (SiO2) with various impurities

Chert (Pink Jasper/Agate variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Pink Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Druzy Quartz (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz

Silicon Dioxide (SiO2)

Green Aventurine (Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)) — metamorphic

Green Aventurine

Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)

Chert (Nodule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Nodule)

Silicon Dioxide (SiO2)

Sandstone Concretion (Ferruginous Sandstone Concretion (Primarily SiO2 with Iron Oxide cement)) — sedimentary

Sandstone Concretion

Ferruginous Sandstone Concretion (Primarily SiO2 with Iron Oxide cement)

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Black Sand (Magnetite Sand) (Magnetite-rich Placers (Fe3O4)) — sedimentary

Black Sand (Magnetite Sand)

Magnetite-rich Placers (Fe3O4)

Sandstone (Sandstone (lithified arenite/wacke)) — Sedimentary Rock

Sandstone

Sandstone (lithified arenite/wacke)

Sedimentary Rock

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — mineral

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Flower Jasper (Agatized Fossil Coral / Chalcedony (SiO2)) — sedimentary

Flower Jasper

Agatized Fossil Coral / Chalcedony (SiO2)

Fossilized Turritella Gastropod (Internal Mold) (Turritella (Fossil Gastropod Crust)) — sedimentary

Fossilized Turritella Gastropod (Internal Mold)

Turritella (Fossil Gastropod Crust)

Greywacke (River Siltstone) (Lithic Sandstone / Greywacke) — sedimentary

Greywacke (River Siltstone)

Lithic Sandstone / Greywacke

Sandstone with Ironstone Concretion (Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))) — sedimentary

Sandstone with Ironstone Concretion

Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))