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.

Quartz Vein in Sedimentary Matrix (Silicon Dioxide (SiO2) with host rock) — mineral

Quartz Vein in Sedimentary Matrix

Silicon Dioxide (SiO2) with host rock

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

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

Chert (Nodule)

Chert (Silicon Dioxide, SiO2)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Chert (SiO2)

Limestone with Calcite Veins (Calcium Carbonate (CaCO3)) — sedimentary

Limestone with Calcite Veins

Calcium Carbonate (CaCO3)

Black Jasper (Silicon Dioxide (SiO2) with Carbonaceous inclusions) — sedimentary

Black Jasper

Silicon Dioxide (SiO2) with Carbonaceous inclusions

Coquina (Biogenic Limestone (Calcite/Aragonite base, CaCO3)) — sedimentary

Coquina

Biogenic Limestone (Calcite/Aragonite base, CaCO3)

Pegmatite (likely Granitic Pegmatite) (Pegmatite (a coarse-grained igneous rock, often with granitic composition)) — igneous

Pegmatite (likely Granitic Pegmatite)

Pegmatite (a coarse-grained igneous rock, often with granitic composition)

Agate (Silicon Dioxide (SiO2) - variety: Chalcedony) — mineral

Agate

Silicon Dioxide (SiO2) - variety: Chalcedony

Brown Jasper (Likely) (Jasper (Cryptocrystalline Silicon Dioxide - SiO2)) — Mineral

Brown Jasper (Likely)

Jasper (Cryptocrystalline Silicon Dioxide - SiO2)

Greenstone (Greenschist (containing chlorite, epidote, and actinolite)) — metamorphic

Greenstone

Greenschist (containing chlorite, epidote, and actinolite)

Native Copper with Cuprite and Quartz (Copper (Cu), Cuprite (Cu2O), Quartz (SiO2)) — mineral

Native Copper with Cuprite and Quartz

Copper (Cu), Cuprite (Cu2O), Quartz (SiO2)

Chert (Jasper variety) (Cryptocrystalline quartz (SiO2)) — sedimentary

Chert (Jasper variety)

Cryptocrystalline quartz (SiO2)

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

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

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

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Moss Agate (Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)) — Mineral

Moss Agate

Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)

Dendritic Agate (Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)) — mineral

Dendritic Agate

Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)

Red Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Red Jasper

Jasper (Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossil Shell Fragment (possibly Brachiopod or Bivalve) (Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca) — sedimentary

Fossil Shell Fragment (possibly Brachiopod or Bivalve)

Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca

Quartz Vein in Host Rock (Gossanous Matrtix) (Silicon Dioxide (SiO2) with iron oxides (Limonite/Hematite)) — mineral

Quartz Vein in Host Rock (Gossanous Matrtix)

Silicon Dioxide (SiO2) with iron oxides (Limonite/Hematite)

Limonite (Iron Ore) (Hydrous ferric oxides (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Hydrous ferric oxides (FeO(OH)·nH2O)

Jasper (Silicon Dioxide (SiO2)) — sedimentary

Jasper

Silicon Dioxide (SiO2)

Banded Agate (Botswana Agate) (Silicon Dioxide (SiO2)) — mineral

Banded Agate (Botswana Agate)

Silicon Dioxide (SiO2)

Fossiliferous Limestone (Calcareous biomicrite / Calcium Carbonate (CaCO3)) — sedimentary

Fossiliferous Limestone

Calcareous biomicrite / Calcium Carbonate (CaCO3)

Coquina or Fossiliferous Limestone (Fossiliferous Calcarenite (CaCO3)) — sedimentary

Coquina or Fossiliferous Limestone

Fossiliferous Calcarenite (CaCO3)

Chert (Field Stone) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Field Stone)

Chert (Silicon Dioxide, SiO2)

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

Chert (varieties include Flint and Jasper)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Shell Cameo (Sardonyx Shell) (Cassis madagascariensis (Sardonyx shell)) — mineral (biogenic silica/calcium carbonate substrate)

Shell Cameo (Sardonyx Shell)

Cassis madagascariensis (Sardonyx shell)

mineral (biogenic silica/calcium carbonate substrate)

Porphyry (Porphyritic Basalt or Porphyritic Andesite) — igneous

Porphyry

Porphyritic Basalt or Porphyritic Andesite

Native Silver (Silver (Ag)) — mineral

Native Silver

Silver (Ag)

Olivine Diabase Porphyry (Porphyritic Olivine-Bearing Diabase (Micro-Gabbro)) — igneous

Olivine Diabase Porphyry

Porphyritic Olivine-Bearing Diabase (Micro-Gabbro)

Chalcedony (Agate/Quartz pebble) (Silicon dioxide (SiO2) - Microcrystalline Quartz) — mineral

Chalcedony (Agate/Quartz pebble)

Silicon dioxide (SiO2) - Microcrystalline Quartz

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

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Garnet (Almandine variety) (Almandine, Fe3Al2(SiO4)3) — Mineral

Garnet (Almandine variety)

Almandine, Fe3Al2(SiO4)3

Banded Gneiss (Gneiss (pronounced "nice")) — Metamorphic Rock

Banded Gneiss

Gneiss (pronounced "nice")

Metamorphic Rock

Rough Emerald (Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)) — mineral

Rough Emerald

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Satin Spar Selenite (Gypsum (CaSO4·2H2O)) — mineral

Satin Spar Selenite

Gypsum (CaSO4·2H2O)

Chert (with Quartz Veining) (Chert (formula: SiO2)) — sedimentary

Chert (with Quartz Veining)

Chert (formula: SiO2)