Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.

Learn about Organic Gemstone (Sedimentary Classification) in the encyclopedia

Sapropel

Bituminous Shale

Bituminous Shale

Black Shale

Red Garnet

Conglomerate

Quartzite Sandstone

Quartzite Sandstone

Breccia

Ironstone

Oil Shale

Jet

Petrified Wood

Amber

Iron meteorite fragment (likely metallic meteorite) (Fe–Ni kamacite/taenite alloy; exact identification requires testing) — meteorite

Iron meteorite fragment (likely metallic meteorite)

Fe–Ni kamacite/taenite alloy; exact identification requires testing

Chert (specifically Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint)

Silicon Dioxide (SiO2)

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

Chert (Jasper/Chalcedony)

Microcrystalline Quartz (SiO2)

Red Chert (Jasper) (Cryptocrystalline Quartz (SiO2) with iron oxide inclusions) — sedimentary

Red Chert (Jasper)

Cryptocrystalline Quartz (SiO2) with iron oxide inclusions

Baltic Amber (Succinite (Fossilized Resin)) — fossil

Baltic Amber

Succinite (Fossilized Resin)

Petrified Wood (Silicified Wood (primarily SiO2)) — mineral

Petrified Wood

Silicified Wood (primarily SiO2)

Weathered river cobble, likely basaltic andesite (Fine-grained mafic volcanic rock; likely basalt or andesite, identification uncertain from image alone) — igneous

Weathered river cobble, likely basaltic andesite

Fine-grained mafic volcanic rock; likely basalt or andesite, identification uncertain from image alone

Pearl (in Marcasite Jewelry) (Biogenic Calcium Carbonate (primarily Aragonite, CaCO3)) — gemstone

Pearl (in Marcasite Jewelry)

Biogenic Calcium Carbonate (primarily Aragonite, CaCO3)

Chert (varieties include Flint and Jasper) (Silicon Dioxide (SiO2) / Microcrystalline Quartz) — sedimentary

Chert (varieties include Flint and Jasper)

Silicon Dioxide (SiO2) / Microcrystalline Quartz

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

Chert (often called Flint in dark varieties)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Tumbled jasper (likely picture jasper) (Jasper, an opaque microcrystalline variety of quartz (SiO₂); exact variety uncertain from the photo) — mineral

Tumbled jasper (likely picture jasper)

Jasper, an opaque microcrystalline variety of quartz (SiO₂); exact variety uncertain from the photo

Small quartz-rich rock fragment (Likely quartz-bearing feldspathic rock; exact identification is limited by the image) — mineral

Small quartz-rich rock fragment

Likely quartz-bearing feldspathic rock; exact identification is limited by the image

Red Chert (Jasper) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Red Chert (Jasper)

Silicon Dioxide (SiO2) with iron oxide inclusions

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

Chert (Jasper)

Cryptocrystalline Quartz (SiO2)

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

Chert (often called Flint or Agate nodule)

Cryptocrystalline Quartz (SiO2)

Jasper (Jasper (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Jasper

Jasper (Cryptocrystalline variety of Quartz, SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Amber (Copal) (Succinite (fossilized resin)) — mineral

Amber (Copal)

Succinite (fossilized resin)

Chert (Blue-Gray Chert) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Blue-Gray Chert)

Microcrystalline quartz (SiO2)

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

Chert (Flint)

Chert (Microcrystalline Silica, SiO2)

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

Chert (Flint/Jasper)

Microcrystalline Quartz (SiO2)

Amber (Raw) (Succinite (Fossilized Resin)) — mineraloid

Amber (Raw)

Succinite (Fossilized Resin)

Possible iron meteorite (Iron–nickel meteorite, commonly kamacite-taenite (Fe-Ni alloy)) — meteorite

Possible iron meteorite

Iron–nickel meteorite, commonly kamacite-taenite (Fe-Ni alloy)

Chert (specifically Flint or Jasper variant) (Microcrystalline silica (SiO2)) — sedimentary

Chert (specifically Flint or Jasper variant)

Microcrystalline silica (SiO2)

Chert Nodule (Microcrystalline Silica (SiO2)) — sedimentary

Chert Nodule

Microcrystalline Silica (SiO2)

Chert (and its variety Flint) (Silicon dioxide (SiO2) / Microcrystalline quartz) — sedimentary

Chert (and its variety Flint)

Silicon dioxide (SiO2) / Microcrystalline quartz

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossil bivalve shell (Likely an extinct or modern-like ribbed cockle/scallop; exact genus requires locality and diagnostic hinge features) — fossil

Fossil bivalve shell

Likely an extinct or modern-like ribbed cockle/scallop; exact genus requires locality and diagnostic hinge features

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

Jasper

Jasper (Silicon Dioxide) - SiO2

Petrified Wood (Silicified wood (Quartz/Chalcedony - SiO2)) — mineral

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Polished banded agate (likely picture jasper or petrified wood) (Microcrystalline quartz, SiO₂, with iron-oxide and clay inclusions) — gemstone

Polished banded agate (likely picture jasper or petrified wood)

Microcrystalline quartz, SiO₂, with iron-oxide and clay inclusions

Pearl (Calcium Carbonate (CaCO3) with Conchiolin) — mineral

Pearl

Calcium Carbonate (CaCO3) with Conchiolin

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

Chert (Jasper/Chalcedony)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Paleoxylon (SiO2)) — fossil

Petrified Wood

Silicified Paleoxylon (SiO2)

Weathered quartz-rich rock, possibly granite or quartzite (Indeterminate quartz–feldspar aggregate; likely weathered granite (quartz, feldspar, minor iron oxides)) — igneous

Weathered quartz-rich rock, possibly granite or quartzite

Indeterminate quartz–feldspar aggregate; likely weathered granite (quartz, feldspar, minor iron oxides)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Chert (specifically Flint or Novaculite variant) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (specifically Flint or Novaculite variant)

Chert (Microcrystalline Quartz, SiO2)

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

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Tahitian Pearl (Black / Pistachio Pearl) (Biogenic Aragonite / Calcite (CaCO3 with conchiolin)) — gemstone

Tahitian Pearl (Black / Pistachio Pearl)

Biogenic Aragonite / Calcite (CaCO3 with conchiolin)

Amber (Raw Copal) (Fossilized Plant Resin (Gummite/Succinite)) — mineral

Amber (Raw Copal)

Fossilized Plant Resin (Gummite/Succinite)

Pearl (Nacre (aragonite, CaCO₃, in an organic conchiolin matrix)) — gemstone

Pearl

Nacre (aragonite, CaCO₃, in an organic conchiolin matrix)