Rock Identifier

Category

Organic Gemstone (Sedimentary Associations)

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

Chert (often called Flint in various colors) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint in various colors)

Silicon Dioxide (SiO2)

Graphite (Graphite (Carbon, C)) — metamorphic

Graphite

Graphite (Carbon, C)

Graphite (Graphite (Native Carbon), Formula: C) — Metamorphic

Graphite

Graphite (Native Carbon), Formula: C

Fossil Coral (Cnidaria Anthozoa (Fossilized)) — sedimentary

Fossil Coral

Cnidaria Anthozoa (Fossilized)

Pyrite (Fool's Gold) (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Stromatolite (Biogenic Sedimentary Rock (composed predominantly of CaCO3)) — sedimentary

Stromatolite

Biogenic Sedimentary Rock (composed predominantly of CaCO3)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Jasper (Silicon dioxide (SiO2) with impurities) — sedimentary

Jasper

Silicon dioxide (SiO2) with impurities

Pyrite in Matrix (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite in Matrix (Fool's Gold)

Iron Disulfide (FeS2)

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Agatized Fossil (Druzy Agate) (Silicon Dioxide (SiO2) replacing organic matter) — sedimentary

Agatized Fossil (Druzy Agate)

Silicon Dioxide (SiO2) replacing organic matter

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

Chert (Jasper/Flint variant)

Microcrystalline Quartz (SiO2)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Fossiliferous Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Fossiliferous Limestone

Calcium Carbonate (CaCO3)

Coquina / Limonite-stained Limestone (Sedimentary Limestone with Iron Oxyhydroxide (FeO(OH)·nH2O)) — sedimentary

Coquina / Limonite-stained Limestone

Sedimentary Limestone with Iron Oxyhydroxide (FeO(OH)·nH2O)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides) — Mineral (Variety of Chalcedony)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides

Mineral (Variety of Chalcedony)

Red Coral (Corallium rubrum (Calcium Carbonate, CaCO3 with Carotenoid pigments)) — Mineraloid (Organic Gemstone)

Red Coral

Corallium rubrum (Calcium Carbonate, CaCO3 with Carotenoid pigments)

Mineraloid (Organic Gemstone)

Amber (Fossilized Tree Resin (Generic formula roughly C10H16O)) — mineral

Amber

Fossilized Tree Resin (Generic formula roughly C10H16O)

Chert (Tan/Yellow variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Tan/Yellow variety)

Microcrystalline quartz (SiO2)

Chert Nodules in Limestone (Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)) — sedimentary

Chert Nodules in Limestone

Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)

Travertine (Calcareous tufa (CaCO3)) — sedimentary

Travertine

Calcareous tufa (CaCO3)

Glauconite (Greensand) ((K, Na)(Fe3⁰, Al, Mg)₂(Si, Al)₄O₁₀(OH)₂) — sedimentary

Glauconite (Greensand)

(K, Na)(Fe3⁰, Al, Mg)₂(Si, Al)₄O₁₀(OH)₂

Brachiopod Fossil in Limestone (Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)) — sedimentary

Brachiopod Fossil in Limestone

Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)

Lepidolite (K(Li,Al)3(Si,Al)4O10(F,OH)2) — Mineral

Lepidolite

K(Li,Al)3(Si,Al)4O10(F,OH)2

Chert (Jasper variation) (Chert (Cryptocrystalline microcrystalline Silicon Dioxide, SiO2)) — sedimentary

Chert (Jasper variation)

Chert (Cryptocrystalline microcrystalline Silicon Dioxide, SiO2)

Amazonite (Amazonite (KAlSi3O8 - a variety of Microcline Feldspar)) — Mineral

Amazonite

Amazonite (KAlSi3O8 - a variety of Microcline Feldspar)

Coquina (Fossiliferous Limestone) (Coquina (Organic Clastic Limestone)) — sedimentary

Coquina (Fossiliferous Limestone)

Coquina (Organic Clastic Limestone)

Limestone with Bitumen/Chert (Calcite (CaCO3) containing organic hydrocarbons) — sedimentary

Limestone with Bitumen/Chert

Calcite (CaCO3) containing organic hydrocarbons

Banded Chert (Silicon Dioxide (SiO2)) — sedimentary

Banded Chert

Silicon Dioxide (SiO2)

Pearl (Biogenic Mineral) (Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3) — mineral

Pearl (Biogenic Mineral)

Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3

Glauconite (Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2) — mineral

Glauconite

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

Larimar (Pectolite (Sodium Calcium Silicate Hydroxide) - (NaCa2(Si3O8)(OH))) — Mineral

Larimar

Pectolite (Sodium Calcium Silicate Hydroxide) - (NaCa2(Si3O8)(OH))

Shale (Fissile mudrock (composed primarily of clay minerals and quartz)) — sedimentary

Shale

Fissile mudrock (composed primarily of clay minerals and quartz)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Fossiliferous Limestone (Limestone with embedded fossil cross-section) — sedimentary

Fossiliferous Limestone

Limestone with embedded fossil cross-section

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

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Chert (Arrowhead Preform or Point) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (Arrowhead Preform or Point)

Chert (Microcrystalline Quartz, SiO2)

Shale (Fissile mudstone (primarily clay minerals and silt-sized quartz)) — sedimentary

Shale

Fissile mudstone (primarily clay minerals and silt-sized quartz)

Amber (Succiniferous fossil resin (C10H16O)) — mineraloid

Amber

Succiniferous fossil resin (C10H16O)

Chert (Jasper) (Silicon dioxide (SiO2)) — sedimentary

Chert (Jasper)

Silicon dioxide (SiO2)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)