Rock Identifier

Category

Sedimentary (Formed From Silica Deposits)

Browse sedimentary (formed from silica deposits) specimens identified by the Rock Identifier community.

Pink Opal / Peruvian Opal (Hydrated amorphous silicon dioxide (SiO2·nH2O)) — Mineral

Pink Opal / Peruvian Opal

Hydrated amorphous silicon dioxide (SiO2·nH2O)

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

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide impurities (Hematite)

Limestone (Calcareous sedimentary rock (primarily Calcium Carbonate, CaCO3)) — sedimentary

Limestone

Calcareous sedimentary rock (primarily Calcium Carbonate, CaCO3)

Black Jasper (Black Stone / River Pebble) (Silicon Dioxide (SiO₂), Opaque variety of Chalcedony) — sedimentary

Black Jasper (Black Stone / River Pebble)

Silicon Dioxide (SiO₂), Opaque variety of Chalcedony

Chert (Jasper/Flint Pebble) (Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Flint Pebble)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)

Leopard Skin Jasper (Jasper (Silicon Dioxide with impurities), SiO2) — sedimentary

Leopard Skin Jasper

Jasper (Silicon Dioxide with impurities), SiO2

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Hematite (Hematite (Fe2O3)) — mineral

Hematite

Hematite (Fe2O3)

Chert (often called Jasper or Flint in this color variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Jasper or Flint in this color variety)

Silicon Dioxide (SiO2)

Blue Apatite (Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

Jasper and Quartzite mix (Silicon Dioxide (SiO2) with impurities) — sedimentary or metamorphic

Jasper and Quartzite mix

Silicon Dioxide (SiO2) with impurities

sedimentary or metamorphic

Wonderstone (Sandstone) (Silicified Quartz Sandstone with Iron Oxide staining) — sedimentary

Wonderstone (Sandstone)

Silicified Quartz Sandstone with Iron Oxide staining

Ironstone (likely Limonite or Goethite nodule) (Hydrothermally altered Ferric Hydroxide (FeO(OH)·nH2O)) — sedimentary

Ironstone (likely Limonite or Goethite nodule)

Hydrothermally altered Ferric Hydroxide (FeO(OH)·nH2O)

Travertine (Calcareous Tufa (CaCO3)) — sedimentary

Travertine

Calcareous Tufa (CaCO3)

Honey Calcite (Calcium Carbonate (CaCO3)) — mineral

Honey Calcite

Calcium Carbonate (CaCO3)

Grey Chalcedony (Tumbled Moon) (Microcrystalline Quartz (SiO2)) — mineral

Grey Chalcedony (Tumbled Moon)

Microcrystalline Quartz (SiO2)

Satin Spar (Gypsum) (Calcium Sulfate Dihydrate (CaSO4·2H2O)) — mineral

Satin Spar (Gypsum)

Calcium Sulfate Dihydrate (CaSO4·2H2O)

Petrified Wood (Silicified Wood (SiO2 permineralization)) — sedimentary

Petrified Wood

Silicified Wood (SiO2 permineralization)

Agate (translucent pebble) (Silicon dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Agate (translucent pebble)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Sandstone (Sandstone (Clastic Sedimentary Rock)) — Sedimentary Rock

Sandstone

Sandstone (Clastic Sedimentary Rock)

Sedimentary Rock

Shale (Fissile Siliciclastic Sedimentary Rock) — sedimentary

Shale

Fissile Siliciclastic Sedimentary Rock

Limonite (Iron Ore) (Limonite (̑FeO(OH)·nH₂O)) — sedimentary

Limonite (Iron Ore)

Limonite (̑FeO(OH)·nH₂O)

Hematite Nodule (Hematite (Fe2O3)) — mineral

Hematite Nodule

Hematite (Fe2O3)

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

Turquoise in Matrix

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

Blue Lace Agate (Chalcedony (Silicon Dioxide, SiO2)) — mineral

Blue Lace Agate

Chalcedony (Silicon Dioxide, SiO2)

Amethyst (Amethyst (Silicon Dioxide - SiO2)) — mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2)

Coal (most likely Bituminous or Anthracite) (Coal (organic sedimentary rock)) — Sedimentary

Coal (most likely Bituminous or Anthracite)

Coal (organic sedimentary rock)

Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Celestite (Celectine) (Strontium sulfate (SrSO4)) — mineral

Celestite (Celectine)

Strontium sulfate (SrSO4)

Vanadinite (Vanadinite (Pb5(VO4)3Cl)) — mineral

Vanadinite

Vanadinite (Pb5(VO4)3Cl)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Baltic Amber (Butterscotch or Egg Yolk Variety) (Succinite (C10H16O)) — Organic Gemstone (fossilized resin)

Baltic Amber (Butterscotch or Egg Yolk Variety)

Succinite (C10H16O)

Organic Gemstone (fossilized resin)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Fossilized Gastropod in Chert/Limestone (Internal mold of Gastropoda (Class) with CaCO3 or SiO2 mineral formula) — sedimentary

Fossilized Gastropod in Chert/Limestone

Internal mold of Gastropoda (Class) with CaCO3 or SiO2 mineral formula

Howlite (Howlite (Ca2B5SiO9(OH)5)) — mineral

Howlite

Howlite (Ca2B5SiO9(OH)5)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Banded Siltstone or Argillite (Siltstone (primarily SiO2 with Al and Fe oxides)) — sedimentary

Banded Siltstone or Argillite

Siltstone (primarily SiO2 with Al and Fe oxides)

Carnelian (Carnelian (Microcrystalline Quartz, SiO2 with Fe2O3 impurities)) — Mineral

Carnelian

Carnelian (Microcrystalline Quartz, SiO2 with Fe2O3 impurities)

Sparkling Druzy Quartz on Matrix (Silicon Dioxide (SiO2) with iron oxide inclusions) — mineral

Sparkling Druzy Quartz on Matrix

Silicon Dioxide (SiO2) with iron oxide inclusions

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Septarian Nodule (Septarian Stone) (Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)) — sedimentary

Septarian Nodule (Septarian Stone)

Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)

Magnetite (Iron Ore) (Magnetite (Fe3O4)) — mineral

Magnetite (Iron Ore)

Magnetite (Fe3O4)