Rock Identifier

Category

Organic Gemstone (Not A Rock)

Browse organic gemstone (not a rock) specimens identified by the Rock Identifier community.

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

Chert (Mudstone)

Microcrystalline Quartz (SiO2)

Chert (Iron-stained) (Microcrystalline silica (SiO2) with trace Iron oxide (Fe2O3)) — sedimentary

Chert (Iron-stained)

Microcrystalline silica (SiO2) with trace Iron oxide (Fe2O3)

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

Chert

Chert (Microcrystalline Quartz, SiO2)

Amber (Succinite (a variety of fossilized tree resin); chemical formula appx. C10H16O) — mineraloid

Amber

Succinite (a variety of fossilized tree resin); chemical formula appx. C10H16O

Pearl (Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3) — mineral

Pearl

Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3

Graphite Schist (C (Carbonaceous Schist)) — metamorphic

Graphite Schist

C (Carbonaceous Schist)

Yellow Chert (Sedimentary cryptocrystalline quartz (SiO2)) — sedimentary

Yellow Chert

Sedimentary cryptocrystalline quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (Yellow or Brown Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow or Brown Jasper)

Microcrystalline Quartz (SiO2)

Amber (Succinicum (Organic polymer, largely C10H16O)) — Organic Mineral

Amber

Succinicum (Organic polymer, largely C10H16O)

Organic Mineral

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)

Yellow Jasper (Silicon Dioxide (SiO2)) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2)

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

Chert (specifically White Chert or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Bituminous Coal (Organic-rich sedimentary rock (Complex hydrocarbons)) — sedimentary

Bituminous Coal

Organic-rich sedimentary rock (Complex hydrocarbons)

Chert (Jasper/Agate variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Agate variety)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Chert / River Pebble (Silicon Dioxide (SiO2)) — sedimentary

Chert / River Pebble

Silicon Dioxide (SiO2)

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

Moss Agate

Chalcedony (Silicon Dioxide - SiO2) with inclusions

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Fossil Coral (Rugose Coral Fragment) (Rugosa (extinct order of solitary and colonial corals)) — sedimentary

Fossil Coral (Rugose Coral Fragment)

Rugosa (extinct order of solitary and colonial corals)

Shale (Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)) — sedimentary

Shale

Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)

Moss Agate (Chalcedony (SiO2) with inclusions of manganese or iron oxides) — mineral

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxides

Pearl (Aragonite / Calcium Carbonate (CaCO3)) — mineral

Pearl

Aragonite / Calcium Carbonate (CaCO3)

Moonstone (Orthoclase (Potassium Aluminum Silicate), Formula: (K,Na)AlSi3O8) — mineral

Moonstone

Orthoclase (Potassium Aluminum Silicate), Formula: (K,Na)AlSi3O8

Chert (Holey Stone) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Holey Stone)

Microcrystalline Quartz (SiO2)

Glauconitic Sandstone (Glauconitic arenite (contains (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone

Glauconitic arenite (contains (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)

Pyrite Geode (Sparkling Druzy) (Iron Sulfide (FeS2) in Sedimentary Nodule) — mineral

Pyrite Geode (Sparkling Druzy)

Iron Sulfide (FeS2) in Sedimentary Nodule

Chert (often called Flint) (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (often called Flint)

Chert (Cryptocrystalline Silica, SiO2)

Chert (often called Flint in archaeological contexts) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint in archaeological contexts)

Silicon Dioxide (SiO2)

Jasper (Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)) — sedimentary

Jasper

Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)

Chert (Dark Variety / Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Dark Variety / Flint)

Silicon Dioxide (SiO2)

River Stone (likely Mudstone or Siltstone) (Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)) — sedimentary

River Stone (likely Mudstone or Siltstone)

Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Iron inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Iron inclusions

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

Agate (Moss or Dendritic Agate)

Chalcedony (Silicon Dioxide, SiO2)

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)

Flower Jasper (Agatized Fossil Coral / Chalcedony (SiO2)) — sedimentary

Flower Jasper

Agatized Fossil Coral / Chalcedony (SiO2)

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

Chert (Flint)

Chert (SiO2)

Schist (N/A (a rock type, not a mineral formula)) — metamorphic

Schist

N/A (a rock type, not a mineral formula)

Chert (Field Stone) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Field Stone)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)