Rock Identifier

Category

Mineral (Silicate Replaced Organic Material)

Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.

Learn about Mineral (Silicate Replaced Organic Material) in the encyclopedia

Calc-Silicate Rock

Calc-Silicate Rock

Talc

Eltyubyuite

Peat

Paracelsian

Black Shale

Petrified Wood

Banalsite

Hemimorphite

Mica

Shattuckite

Skarn

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood) (Silicified Wood (primarily Chalcedony/Quartz, SiO2)) — mineral

Petrified Wood (Silicified Wood)

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Yellow-brown jasper or silicified volcanic rock (Microcrystalline quartz (chalcedony), SiO₂, likely jasper) — mineral

Yellow-brown jasper or silicified volcanic rock

Microcrystalline quartz (chalcedony), SiO₂, likely jasper

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

Chert / Chalcedony

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Smelter Slag (Anthropogenic Silicate Slag) — igneous

Smelter Slag

Anthropogenic Silicate Slag

Chert (often called Flint or Agate nodule) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Agate nodule)

Cryptocrystalline Quartz (SiO2)

Unidentified gray rock fragment (Indeterminate from image; possibly quartz- or feldspar-rich silicate material) — mineral

Unidentified gray rock fragment

Indeterminate from image; possibly quartz- or feldspar-rich silicate material

Petrified Wood (Silicified Wood) (Silicified fossil wood (SiO2)) — metamorphic

Petrified Wood (Silicified Wood)

Silicified fossil wood (SiO2)

Chert (Flint) (Chert (SiO2)) — sedimentary

Chert (Flint)

Chert (SiO2)

Petrified Wood (Silicified wood (primarily Silicon Dioxide - SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily Silicon Dioxide - SiO2)

Jasper (Red Jasper) (Silicon Dioxide (SiO₂)) — sedimentary

Jasper (Red Jasper)

Silicon Dioxide (SiO₂)

Petrified Wood (Silicified Wood (primarily SiO2 - Silicon Dioxide)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Tektite (Impactite (Natural Silicate Glass)) — meteorite

Tektite

Impactite (Natural Silicate Glass)

Likely weathered gray stone or chert fragment (Uncertain; possibly microcrystalline quartz (SiO₂)-rich chert) — sedimentary

Likely weathered gray stone or chert fragment

Uncertain; possibly microcrystalline quartz (SiO₂)-rich chert

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Polished ocean jasper / orbicular jasper (Silicified rhyolite or chalcedony-rich microcrystalline quartz (SiO₂), commonly sold as ocean jasper) — sedimentary

Polished ocean jasper / orbicular jasper

Silicified rhyolite or chalcedony-rich microcrystalline quartz (SiO₂), commonly sold as ocean jasper

Fossil oyster shell (Ostrea or Exogyra sp. (identification uncertain)) — fossil

Fossil oyster shell

Ostrea or Exogyra sp. (identification uncertain)

Blue-gray limestone or marble fragment (Calcite-rich carbonate rock; likely calcitic marble (CaCO₃), though limestone is possible) — metamorphic

Blue-gray limestone or marble fragment

Calcite-rich carbonate rock; likely calcitic marble (CaCO₃), though limestone is possible

Chert / Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Jasper

Microcrystalline Quartz (SiO2)

Green Moss Agate (Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite) — mineral

Green Moss Agate

Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite

Chert Concretion (Microcrystalline Quartz (SiO2) in Carbonate Matrix) — sedimentary

Chert Concretion

Microcrystalline Quartz (SiO2) in Carbonate Matrix

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

Chert (Nodule)

Silicon Dioxide (SiO2)

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

Jasper (specifically Yellow Jasper and Red Jasper)

Silicon Dioxide (SiO2) with iron oxide inclusions

Polished tiger’s-eye (Quartz variety, SiO₂, with crocidolite-derived iron inclusions) — mineral

Polished tiger’s-eye

Quartz variety, SiO₂, with crocidolite-derived iron inclusions

Chert (Jasper-like Silicate) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper-like Silicate)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Banded chert or flint (Microcrystalline quartz (SiO₂), commonly called chert/flint) — sedimentary

Banded chert or flint

Microcrystalline quartz (SiO₂), commonly called chert/flint

Fossilized tooth, likely mammalian molar (Silicified or mineral-replaced mammalian tooth; exact taxon cannot be determined from the image) — fossil

Fossilized tooth, likely mammalian molar

Silicified or mineral-replaced mammalian tooth; exact taxon cannot be determined from the image

Likely weathered igneous rock fragments (Indeterminate; possibly basaltic or granitic rock with quartz, feldspar, and dark mafic minerals) — igneous

Likely weathered igneous rock fragments

Indeterminate; possibly basaltic or granitic rock with quartz, feldspar, and dark mafic minerals

Fossilized Coral (Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)) — sedimentary

Fossilized Coral

Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)

Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

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

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Chert (Jasper variety) (Silicon dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon dioxide (SiO2)

Petrified Wood (Silicified Wood (primarily Silicon Dioxide, SiO2)) — mineral

Petrified Wood

Silicified Wood (primarily Silicon Dioxide, SiO2)

Petrified Wood (Silicified wood (Quartz / Chalcedonized wood, SiO2)) — sedimentary

Petrified Wood

Silicified wood (Quartz / Chalcedonized wood, SiO2)

Fossil tooth fragment (Likely fossilized shark tooth or marine vertebrate tooth; exact taxon cannot be determined from the image) — fossil

Fossil tooth fragment

Likely fossilized shark tooth or marine vertebrate tooth; exact taxon cannot be determined from the image

Fossilized Bone (Permineralized Vertebrate Bone) — fossil

Fossilized Bone

Permineralized Vertebrate Bone

Limonite (Ironstone) (Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))) — mineral

Limonite (Ironstone)

Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))

Trilobite fossil in matrix (Trilobita (arthropod fossil; exact species cannot be determined from the image)) — fossil

Trilobite fossil in matrix

Trilobita (arthropod fossil; exact species cannot be determined from the image)