Rock Identifier

Category

Organic Gemstone (Often Associated With Sedimentary Sequences)

Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.

Learn about Organic Gemstone (Often Associated With Sedimentary Sequences) in the encyclopedia

Sapropel

Bituminous Shale

Bituminous Shale

Turbidite

Black Shale

Ironstone

Oil Shale

Jet

Limestone

Sandstone

Pegmatite

Euxenite

Pyroxenite

Sandstone (with carbonaceous plant fragments) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (with carbonaceous plant fragments)

Arenite (composed primarily of SiO2)

Petrified Wood (Silicified Paleoxylon (SiO2)) — fossil

Petrified Wood

Silicified Paleoxylon (SiO2)

Chrome Diopside (Magnesium Calcium Silicate (MgCaSi2O6) containing Chromium impurities) — mineral

Chrome Diopside

Magnesium Calcium Silicate (MgCaSi2O6) containing Chromium impurities

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

Chert (and Flint)

Silicon Dioxide (SiO2)

Limestone with Fossil Fragment (Sedimentary carbonate rock (CaCO3)) — sedimentary

Limestone with Fossil Fragment

Sedimentary carbonate rock (CaCO3)

Unakite (Epidote in Feldspar/Quartz) (Unakite (composed of Epidote {Ca2(Al,Fe)3(SiO4)3(OH)}, Orthoclase {KAlSi3O8}, and Quartz {SiO2})) — metamorphic

Unakite (Epidote in Feldspar/Quartz)

Unakite (composed of Epidote {Ca2(Al,Fe)3(SiO4)3(OH)}, Orthoclase {KAlSi3O8}, and Quartz {SiO2})

Ferruginous Sandstone (Ironstone) (Sedimentary rock with Limonite/Goethite cement) — sedimentary

Ferruginous Sandstone (Ironstone)

Sedimentary rock with Limonite/Goethite cement

Pyrite (Pseudomorph) (Iron Sulfide (FeS2)) — mineral

Pyrite (Pseudomorph)

Iron Sulfide (FeS2)

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

Chert (Jasper)

Cryptocrystalline Quartz (SiO2)

Polished dark chert or flint (Microcrystalline quartz (SiO₂), commonly called chert; possibly flint) — sedimentary

Polished dark chert or flint

Microcrystalline quartz (SiO₂), commonly called chert; possibly flint

Sodalite (Na8(Al6Si6O24)Cl2 (Tectosilicate / Tectofeldspathoid)) — mineral

Sodalite

Na8(Al6Si6O24)Cl2 (Tectosilicate / Tectofeldspathoid)

Banded Chert (Silicon Dioxide (SiO2)) — sedimentary

Banded Chert

Silicon Dioxide (SiO2)

Agate (Chalcedony (SiO2)) — sedimentary

Agate

Chalcedony (SiO2)

Unakite Granite (Unakite (Epidotized Granite)) — metamorphic

Unakite Granite

Unakite (Epidotized Granite)

Sodalite (Sodalite (Na8(Al6Si6O24)Cl2)) — mineral

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Fossiliferous Limestone (Calcium Carbonate (CaCO3) with fossil inclusions) — sedimentary

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with fossil inclusions

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Fossil Shell (Bivalve) (Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)) — sedimentary

Fossil Shell (Bivalve)

Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)

Pyrite-bearing rock (likely pyrite in a quartz or sulfide-rich matrix) (Pyrite, FeS₂; the gray host may be quartz, carbonate, or another sulfide-bearing rock) — mineral

Pyrite-bearing rock (likely pyrite in a quartz or sulfide-rich matrix)

Pyrite, FeS₂; the gray host may be quartz, carbonate, or another sulfide-bearing rock

Chert (often called Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint)

Silicon Dioxide (SiO2)

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

Chert (Flint)

Chert (SiO2)

Jasper (Silicon dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper

Silicon dioxide (SiO2) with iron oxide inclusions

Chert (varieties include Flint and Jasper) (Silicon dioxide (SiO2)) — sedimentary

Chert (varieties include Flint and Jasper)

Silicon dioxide (SiO2)

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

Chert (Jasper)

Microcrystalline Quartz (SiO2)

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

Chert (Black Flint)

Silicon Dioxide (SiO2)

Geode (unopened) (Chert / Chalcedony Geode (SiO2)) — sedimentary

Geode (unopened)

Chert / Chalcedony Geode (SiO2)

Chert (Pebble) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (Pebble)

Chert (Microcrystalline Quartz, SiO2)

Chert (Jasper variety) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

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

Chert (often called Flint when dark)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

Banded Chert (Silicon dioxide (SiO2) with impurities) — sedimentary

Banded Chert

Silicon dioxide (SiO2) with impurities

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

Chert (White Chert)

Microcrystalline Quartz (SiO2)

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

Chert (Yellow Jasper variant)

Microcrystalline quartz (SiO2)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

Map Jasper (Grey Picasso Jasper) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Map Jasper (Grey Picasso Jasper)

Silicon Dioxide (SiO2) with impurities

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

Amber (Raw Copal)

Fossilized Plant Resin (Gummite/Succinite)

Chert Nodules (Chert (SiO2)) — sedimentary

Chert Nodules

Chert (SiO2)

Dendritic Agate (Silicon Dioxide with inclusions (SiO2 + Mn/Fe)) — mineral

Dendritic Agate

Silicon Dioxide with inclusions (SiO2 + Mn/Fe)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Polished hematite-rich ironstone (Hematite (Fe₂O₃), likely mixed with magnetite and iron-rich jasper) — mineral

Polished hematite-rich ironstone

Hematite (Fe₂O₃), likely mixed with magnetite and iron-rich jasper

Chert Arrowhead (Projectile Point) (Microcrystalline Quartz (Chert/Flint)) — sedimentary

Chert Arrowhead (Projectile Point)

Microcrystalline Quartz (Chert/Flint)

Amber (Succinate (Fossilized Tree Resin)) — gemstone

Amber

Succinate (Fossilized Tree Resin)