Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

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

Crushed Limestone (Calcite-rich Sedimentary Rock (CaCO3)) — sedimentary

Crushed Limestone

Calcite-rich Sedimentary Rock (CaCO3)

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

Chert (Iron-stained)

Chert (primarily Microcrystalline Quartz, SiO2)

Chert (Tan/Grey variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Tan/Grey variety)

Silicon Dioxide (SiO2)

Chert (often called Flint or Jasper locally) (Chert (Microcrystalline Quartz, Formula: SiO2)) — sedimentary

Chert (often called Flint or Jasper locally)

Chert (Microcrystalline Quartz, Formula: SiO2)

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

Travertine (often colloquially called Tufa)

Chemical Sedimentary Calcium Carbonate (CaCO3)

Chert (and/or Flint) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (and/or Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

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

Chert (specifically Flint or Common Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Iron-stained or Jasperoid Chert) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Iron-stained or Jasperoid Chert)

Microcrystalline Quartz (SiO2)

Chert / Flint Nodules (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert / Flint Nodules

Cryptocrystalline Quartz (SiO2)

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

Chert (Yellow Jasper/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Nodule)

Microcrystalline Quartz (SiO2)

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

Chert (Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

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

Chert (Grey Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (and Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Chert (specifically Black Chert or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petoskey Stone (Hexagonaria percarinata (Fossilized Rugose Coral)) — sedimentary

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

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

Chert (Flint)

Silicon Dioxide (SiO2)

Tufa (Calcareous Tufa (Calcium Carbonate, CaCO3)) — sedimentary

Tufa

Calcareous Tufa (Calcium Carbonate, CaCO3)

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

Petrified Wood

Silicified Wood (primarily SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO₂)

Moss Agate (Silicon Dioxide with inclusions (SiO2 + impurities)) — mineral

Moss Agate

Silicon Dioxide with inclusions (SiO2 + impurities)

Chert (varietal: Jasper or Flint) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (varietal: Jasper or Flint)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chert (Jasper-bearing) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Jasper-bearing)

Chert (Silicon Dioxide, SiO2)

Almandine Garnet in Matrix (Almandine, Fe3Al2(SiO4)3) — metamorphic

Almandine Garnet in Matrix

Almandine, Fe3Al2(SiO4)3

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Ferruginous Sandstone (Ironstone) (Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)) — sedimentary

Ferruginous Sandstone (Ironstone)

Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

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

Chert (Chert Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Jasper/Flint variant) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Flint variant)

Silicon Dioxide (SiO2)

Amber (Succinite (with empirical formula approximately C10H16O)) — Organic Mineraloid

Amber

Succinite (with empirical formula approximately C10H16O)

Organic Mineraloid

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

Chert (Flint variety)

Chert (Microcrystalline or Cryptocrystalline 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)

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

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Chert (variant Flint/Jasper)

Microcrystalline Opaline Silica (SiO2)

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — mineral

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Bituminous Coal (Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)) — sedimentary

Bituminous Coal

Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)

Limestone with Quartz/Calcite Veins (Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)) — sedimentary

Limestone with Quartz/Calcite Veins

Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)

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

Petrified Wood

Silicified Wood (primarily SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)