Rock Identifier

Category

Organic Crystal (Mineraloid)

Browse organic crystal (mineraloid) specimens identified by the Rock Identifier community.

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides

Purple Agate (Dyed Chalcedony) (SiO2 (Silicon Dioxide) with organic dyes) — mineral

Purple Agate (Dyed Chalcedony)

SiO2 (Silicon Dioxide) with organic dyes

Dyed Pink Quartzite (Jadeite Simulant) (Silicon Dioxide (SiO2) with organic dye) — metamorphic

Dyed Pink Quartzite (Jadeite Simulant)

Silicon Dioxide (SiO2) with organic dye

Red Jasper (Microcrystalline Quartz (Chalcedony), SiO2 with iron oxide inclusions) — sedimentary

Red Jasper

Microcrystalline Quartz (Chalcedony), SiO2 with iron oxide inclusions

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

Limestone

Calcium Carbonate (CaCO3) / Limestone

Chert (Red/Pink variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Red/Pink variety)

Microcrystalline quartz (SiO2)

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

Chert (Flint/Jasper variety)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified wood (primarily SiO2)

Chert (Flint nodule) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Flint nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Limestone with Iron Oxide Staining (Sedimentary Rock (Calcite, CaCO3)) — sedimentary

Limestone with Iron Oxide Staining

Sedimentary Rock (Calcite, CaCO3)

Moss Agate (Silicon Dioxide (Chalcedony with green mineral inclusions), SiO2) — gemstone

Moss Agate

Silicon Dioxide (Chalcedony with green mineral inclusions), SiO2

Oyster Shell Fragment (Crassostrea virginica (or related Bivalvia)) — fossil

Oyster Shell Fragment

Crassostrea virginica (or related Bivalvia)

Sandstone with Vitrinite/Coal inclusions (Arenite with Carbonaceous inclusions) — sedimentary

Sandstone with Vitrinite/Coal inclusions

Arenite with Carbonaceous inclusions

Moss Agate with Jasper (Chalcedony (SiO2 with inclusions)) — mineral

Moss Agate with Jasper

Chalcedony (SiO2 with inclusions)

Fossiliferous Limestone (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Amber (Dark/Black Variety) (Succinite (Resinite), C10H16O) — mineral

Amber (Dark/Black Variety)

Succinite (Resinite), C10H16O

Mother of Pearl (Nacre) (Calcium Carbonate (Aragonite) with organic conchiolin) — gemstone

Mother of Pearl (Nacre)

Calcium Carbonate (Aragonite) with organic conchiolin

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

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Fossilized Echinoid (Sea Urchin) (Echinoidea (Class) - Often found as Micraster or Clypeaster specimens) — sedimentary

Fossilized Echinoid (Sea Urchin)

Echinoidea (Class) - Often found as Micraster or Clypeaster specimens

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

Chert (Jasper variety)

Chert (Silicon Dioxide, SiO2)

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

Chert (Nodule)

Chert (Silicon Dioxide, SiO2)

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

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Chert (SiO2)

Chert (Jasper) (Microcrystalline Quartz (SiO2) with iron oxide impurities) — sedimentary

Chert (Jasper)

Microcrystalline Quartz (SiO2) with iron oxide impurities

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Amber (Succinite (fossilized tree resin)) — fossil

Amber

Succinite (fossilized tree resin)

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Pearls (Pearl: biomineralized aragonite (CaCO₃) and conchiolin) — gemstone

Pearls

Pearl: biomineralized aragonite (CaCO₃) and conchiolin

Petrified Wood (Silicified wood (primarily Quartz, SiO2)) — fossil

Petrified Wood

Silicified wood (primarily Quartz, SiO2)

Limestone Boulder (Sedimentary Rock (Calcium Carbonate, CaCO3)) — sedimentary

Limestone Boulder

Sedimentary Rock (Calcium Carbonate, CaCO3)

Chert (Flint) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline Silica (SiO2)

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

Red Chert (Jasper)

Silicon Dioxide (SiO2)

Geode (Unopened) (Silica-rich concretion (SiO2)) — sedimentary

Geode (Unopened)

Silica-rich concretion (SiO2)

Chert (Yellow Chert/Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Chert/Flint)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Jasper (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper

Silicon Dioxide (SiO2) with impurities

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

Chert (Yellow Jasper/Flint)

Microcrystalline Quartz (SiO2)

Chert (Chert (SiO2)) — sedimentary

Chert

Chert (SiO2)

Chert (Tan/Yellow variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Tan/Yellow variety)

Microcrystalline quartz (SiO2)

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

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (specifically Flint or Jasper variant) (Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)