Rock Identifier

Category

Organic Gemstone (Fossilized Resin)

Browse organic gemstone (fossilized resin) specimens identified by the Rock Identifier community.

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

Stromatolite

Biogenic Sedimentary Rock (composed predominantly of CaCO3)

Coal (Bituminous or Anthracite) (Carbonaceous sedimentary rock (primarily Carbon, C)) — sedimentary

Coal (Bituminous or Anthracite)

Carbonaceous sedimentary rock (primarily Carbon, C)

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

Coquina (Fossiliferous Limestone)

Coquina (Organic Clastic Limestone)

Coal (likely Bituminous or Lignite) (Organic Sedimentary Rock (Carbonaceous)) — sedimentary

Coal (likely Bituminous or Lignite)

Organic Sedimentary Rock (Carbonaceous)

Travertine (Calcareous tufa (CaCO3)) — sedimentary

Travertine

Calcareous tufa (CaCO3)

Coal (most likely Bituminous or Anthracite) (Coal (organic sedimentary rock)) — Sedimentary

Coal (most likely Bituminous or Anthracite)

Coal (organic sedimentary rock)

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)

Shungite (Non-crystalline carbon (allotrope of carbon)) — metamorphic

Shungite

Non-crystalline carbon (allotrope of carbon)

Tree Agate (also known as Dendritic Agate) (Silicon Dioxide with inclusions (SiO2 + Mn/Fe)) — mineral

Tree Agate (also known as Dendritic Agate)

Silicon Dioxide with inclusions (SiO2 + Mn/Fe)

Banded Chert (Sedimentary Cryptocrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Sedimentary Cryptocrystalline Quartz (SiO2)

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

Dendritic Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions

Sandstone Concretion with Fossil Wood (Ferruginous Sandstone Concretion (SiO2 with Fe2O3 cement)) — sedimentary

Sandstone Concretion with Fossil Wood

Ferruginous Sandstone Concretion (SiO2 with Fe2O3 cement)

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

Chert (Jasper)

Silicon dioxide (SiO2)

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

Chert (Jasper variety)

Microcrystalline Quartz (SiO2)

Nacre (Mother of Pearl) (Nacre (Biogenic Aragonite/Calcite composite, CaCO3)) — mineral

Nacre (Mother of Pearl)

Nacre (Biogenic Aragonite/Calcite composite, CaCO3)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Shungite (Non-crystalline carbon (Fullerenes)) — metamorphic

Shungite

Non-crystalline carbon (Fullerenes)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Baroque Pearl (Biogenic Calcium Carbonate (Aragonite/Conchiolin)) — mineral

Baroque Pearl

Biogenic Calcium Carbonate (Aragonite/Conchiolin)

Fossil Crab (Decapoda (likely Avitelmessus or Raninidae family)) — sedimentary

Fossil Crab

Decapoda (likely Avitelmessus or Raninidae family)

Pyritized Ammonite (Ammonitida (replaced by Iron Disulfide, FeS2)) — sedimentary

Pyritized Ammonite

Ammonitida (replaced by Iron Disulfide, FeS2)

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

Coquina or Fossiliferous Limestone

Fossiliferous Calcarenite (CaCO3)

Zebra Rock / Zebra Marble (Banded Limestone-Marble Transition) — metamorphic

Zebra Rock / Zebra Marble

Banded Limestone-Marble Transition

Garden Quartz (Included Quartz (SiO2 with accessory minerals such as Chlorite, Hematite, or Feldspar)) — mineral

Garden Quartz

Included Quartz (SiO2 with accessory minerals such as Chlorite, Hematite, or Feldspar)

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert Pebble Map (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble Map

Microcrystalline Quartz (SiO2)

Green Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Green Chert

Microcrystalline Quartz (SiO2)

Pyrite Geode (Iron Disulfide (FeS2)) — mineral

Pyrite Geode

Iron Disulfide (FeS2)

Chert (Arrowhead Artifact) (Chert (SiO2)) — sedimentary

Chert (Arrowhead Artifact)

Chert (SiO2)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

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

Chert (Jasper)

Silicon Dioxide (SiO2)

Ferruginous Sandstone (with possible trace fossils) (Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)) — sedimentary

Ferruginous Sandstone (with possible trace fossils)

Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)

Opalite (a synthetic glass, often confused with Opal) (Silicon dioxide glass (SiO2nH2O, for natural opal)) — Synthetic (glass)

Opalite (a synthetic glass, often confused with Opal)

Silicon dioxide glass (SiO2nH2O, for natural opal)

Synthetic (glass)

Chalcedony (Common Opal variant) (Silicon dioxide (SiO2) with varying levels of hydration) — mineral

Chalcedony (Common Opal variant)

Silicon dioxide (SiO2) with varying levels of hydration

Chert (or Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (or Chalcedony)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline silica (SiO2)

Banded Chert (Silicon Dioxide (SiO2)) — sedimentary

Banded Chert

Silicon Dioxide (SiO2)

Jasper Agate (Silicon dioxide (SiO2)) — mineral

Jasper Agate

Silicon dioxide (SiO2)

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

Chert (Jasper variation)

Microcrystalline Quartz (SiO2)

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

Pyrite (Fool's Gold) Cube

Iron Sulfide (FeS2)

Limestone (Fossiliferous) (Calcium Carbonate (CaCO3) - Bioclastic Limestone) — sedimentary

Limestone (Fossiliferous)

Calcium Carbonate (CaCO3) - Bioclastic Limestone