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.

Travertine (often colloquially called Tufa) (Chemical Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Travertine (often colloquially called Tufa)

Chemical Sedimentary Calcium Carbonate (CaCO3)

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Prehnite (Prehnite - Ca2Al(AlSi3O10)(OH)2) — mineral

Prehnite

Prehnite - Ca2Al(AlSi3O10)(OH)2

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically a weathered Chert nodule or fragment) (Chert; Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically a weathered Chert nodule or fragment)

Chert; Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper (Petrified Wood variant) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper (Petrified Wood variant)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (specifically Red Chert/Jasper nodule) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Red Chert/Jasper nodule)

Microcrystalline Quartz (SiO2)

Carnelian (Carnelian (variety of Chalcedony, SiO2)) — mineral

Carnelian

Carnelian (variety of Chalcedony, SiO2)

Red Jasper (Jasper (Silicate Mineral), SiO2 with Fe2O3 inclusions) — sedimentary

Red Jasper

Jasper (Silicate Mineral), SiO2 with Fe2O3 inclusions

Rhyolite (Rhyolite) — igneous

Rhyolite

Rhyolite

Amber (Amber (C10H16O)) — mineral

Amber

Amber (C10H16O)

Quartz (likely tumbled or naturally water-worn) (Quartz (SiO₂ - Silicon Dioxide)) — Mineral

Quartz (likely tumbled or naturally water-worn)

Quartz (SiO₂ - Silicon Dioxide)

Petrified Wood (Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)) — sedimentary

Petrified Wood

Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)

Chert (variations include Flint or Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (variations include Flint or Jasper)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

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

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions

Chert (Jasper/Flint Pebble) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Flint Pebble)

Microcrystalline quartz (SiO2)

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

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 (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Blue Tiger's Eye (Crocidolite in Quartz (altered)) — Mineral

Blue Tiger's Eye

Crocidolite in Quartz (altered)

Green Fluorite (Fluorite (Calcium Fluoride - CaF2)) — mineral

Green Fluorite

Fluorite (Calcium Fluoride - CaF2)

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

Chert (Fossiliferous)

Silicon Dioxide (SiO2)

Chert (and/or River Pebble) (Microcrystalline silica (SiO2)) — sedimentary

Chert (and/or River Pebble)

Microcrystalline silica (SiO2)

Chert (Common Opal/Jasper variety) (Microcrystalline Quartz (SiO2) with hydration) — sedimentary

Chert (Common Opal/Jasper variety)

Microcrystalline Quartz (SiO2) with hydration

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

Chert (Jasper type)

Microcrystalline Quartz (SiO2)

Chert (Flint nodule) (Silicon dioxide (SiO2)) — sedimentary

Chert (Flint nodule)

Silicon dioxide (SiO2)

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

Chert (Green variety)

Chert (Silicon Dioxide, SiO2)

Labradorite (Labradorite (Plagioclase Feldspar Series) - (Ca, Na)(Al, Si)4O8) — mineral

Labradorite

Labradorite (Plagioclase Feldspar Series) - (Ca, Na)(Al, Si)4O8

Chert (and Flint) (Silicon dioxide (SiO2) - Microcrystalline quartz) — sedimentary

Chert (and Flint)

Silicon dioxide (SiO2) - Microcrystalline quartz

Chert (often called Flint or Jasper) (Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)

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

Chert (Nodule)

Silicon Dioxide (SiO2)

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

Chert (Pink Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Chert (specifically Black Chert or Flint) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Black Chert or Flint)

Cryptocrystalline Quartz (SiO2)

Chert (Tan or Buffer variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Tan or Buffer variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Chalcedony)

Microcrystalline Quartz (SiO2)

Chert / Flint (Microcrystalline or cryptocrystalline quartz (SiO2)) — sedimentary

Chert / Flint

Microcrystalline or cryptocrystalline quartz (SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

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

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)