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

Wonderstone (Liesegang Sandstone) (Silicified Sandstone with Liesegang Rings (SiO2 + FeO(OH))) — sedimentary

Wonderstone (Liesegang Sandstone)

Silicified Sandstone with Liesegang Rings (SiO2 + FeO(OH))

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Baltic Amber (Succinite (Fossilized Tree Resin)) — fossil

Baltic Amber

Succinite (Fossilized Tree Resin)

Banded Agate (Tumbled) (Silicon Dioxide (SiO2)) — sedimentary

Banded Agate (Tumbled)

Silicon Dioxide (SiO2)

Fossilized Wood (with Coal and Limonite) (Petrified Wood (Silicified or Carbonized Flora)) — sedimentary

Fossilized Wood (with Coal and Limonite)

Petrified Wood (Silicified or Carbonized Flora)

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

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Chalcopyrite (Chalcopyrite (CuFeS2)) — mineral

Chalcopyrite

Chalcopyrite (CuFeS2)

Peridot (Olivine ((Mg,Fe)2SiO4)) — Mineral

Peridot

Olivine ((Mg,Fe)2SiO4)

Weathered River Rock (likely Chert or Basalt with algae) (Silicon dioxide (SiO2) with organic biofilm) — sedimentary

Weathered River Rock (likely Chert or Basalt with algae)

Silicon dioxide (SiO2) with organic biofilm

Chert / Flint (Cryptocrystalline quartz (SiO2)) — sedimentary

Chert / Flint

Cryptocrystalline quartz (SiO2)

Chert (variant Flint/Jasper) (Microcrystalline Opaline Silica (SiO2)) — sedimentary

Chert (variant Flint/Jasper)

Microcrystalline Opaline Silica (SiO2)

Crazy Lace Agate (Chalcedony (SiO2)) — mineral

Crazy Lace Agate

Chalcedony (SiO2)

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

Banded Chert (or Flint)

Microcrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Chert (Chert Pebble) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Chert Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Banded Chert (River Siltstone) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert (River Siltstone)

Microcrystalline Quartz (SiO2)

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

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (primarily Chalcedony or Quartz, SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Chalcedony or Quartz, SiO2)

Chert (Green variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Green variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Amber Dragonfly Brooch (Succinited (Baltic Amber)) — fossil

Amber Dragonfly Brooch

Succinited (Baltic Amber)

Fossilized Bone (Permineralized Bone (Vertebrate Fossil)) — fossil

Fossilized Bone

Permineralized Bone (Vertebrate Fossil)

Fossil Coral (Rugose Coral Fragment) (Rugosa (extinct order of solitary and colonial corals)) — sedimentary

Fossil Coral (Rugose Coral Fragment)

Rugosa (extinct order of solitary and colonial corals)

Chert (Iron-stained) (Chert (SiO2)) — sedimentary

Chert (Iron-stained)

Chert (SiO2)

Anthracite (Anthracite Coal (Carbon)) — sedimentary

Anthracite

Anthracite Coal (Carbon)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Red Sandstone with Reduction Spot (Quartzose Sandstone with a Leach/Reduction Spot) — sedimentary

Red Sandstone with Reduction Spot

Quartzose Sandstone with a Leach/Reduction Spot

Glauconitic Sandstone (Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2 in Quartz Sandstone) — sedimentary

Glauconitic Sandstone

Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2 in Quartz Sandstone

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

Red Jasper (Polished)

Silicon Dioxide (SiO2) with Hematite inclusions

Chert (River Siltstone/Quartzite type) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (River Siltstone/Quartzite type)

Microcrystalline Quartz (SiO2)

Garnet-bearing Schist (Almandine Garnet [Fe3Al2(SiO4)3] in Micaceous Schist) — metamorphic

Garnet-bearing Schist

Almandine Garnet [Fe3Al2(SiO4)3] in Micaceous Schist

Clear Quartz (Quartz (Silicon Dioxide, SiO2)) — Mineral

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Petrified Wood (Silicified wood (Quartz/Chalcedony replacement of cellulose)) — fossil

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement of cellulose)

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

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Unakite (Epidotized Granite) — metamorphic

Unakite

Epidotized Granite

Unakite (Unakite (Epidotized Granite)) — metamorphic

Unakite

Unakite (Epidotized Granite)

Unakite (Epidotized Granite) — metamorphic

Unakite

Epidotized Granite

Amazonite (likely mixed with other feldspars/minerals) (Amazonite is a variety of Microcline, which is a tectosilicate mineral, formula KAISi3O8. The mixed beads could include other feldspars or quartz.) — Mineral

Amazonite (likely mixed with other feldspars/minerals)

Amazonite is a variety of Microcline, which is a tectosilicate mineral, formula KAISi3O8. The mixed beads could include other feldspars or quartz.

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Raw Quartz (Silicon Dioxide (SiO2)) — mineral

Raw Quartz

Silicon Dioxide (SiO2)

Chalcedony (Agate/Seashell replacement) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Chalcedony (Agate/Seashell replacement)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)