Rock Identifier

Category

Organic Gemstone (Not A Rock)

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

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

Shale

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

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

Stromatolite

Biogenic Sedimentary Rock (composed predominantly of CaCO3)

Pyrite in Shale (Iron Disulfide (FeS2) in Argillaceous Shale) — sedimentary

Pyrite in Shale

Iron Disulfide (FeS2) in Argillaceous Shale

Chert (specifically Flint or Gray Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Gray Chalcedony)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Red Jasper (Jasper (Silicon Dioxide with Iron inclusions - SiO2)) — Sedimentary/Metamorphic

Red Jasper

Jasper (Silicon Dioxide with Iron inclusions - SiO2)

Sedimentary/Metamorphic

Amber (Succinite (specifically for Baltic amber); Chemical formula approximately C10H16O) — mineral

Amber

Succinite (specifically for Baltic amber); Chemical formula approximately C10H16O

Amber (Succinite (Resinous fossilized tree sap)) — Mineraloid

Amber

Succinite (Resinous fossilized tree sap)

Green Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Green Chert

Microcrystalline Quartz (SiO2)

Jasper (Silicon Dioxide (SiO2) with iron oxide impurities) — sedimentary

Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

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

Chert (Nodule)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Carnelian Agate (Silicon Dioxide (SiO2) - variety of Chalcedony) — mineral

Carnelian Agate

Silicon Dioxide (SiO2) - variety of Chalcedony

Tiger's Eye (SiO2 (Silicon Dioxide with inclusions of Goethite/Limonite)) — Metamorphic

Tiger's Eye

SiO2 (Silicon Dioxide with inclusions of Goethite/Limonite)

Jasper (Silicon dioxide / Chalcedony (SiO2)) — Sedimentary

Jasper

Silicon dioxide / Chalcedony (SiO2)

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Jasper (Imperial Jasper style) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper (Imperial Jasper style)

Silicon Dioxide (SiO2) with impurities

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

Tiger's Eye (likely Hawk's Eye variant)

Pseudomorph of Quartz after Crocidolite (SiO2)

Jasper (Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)) — sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)

Pearl (Organic Mineraloid (CaCO3 + Conchiolin)) — mineral

Pearl

Organic Mineraloid (CaCO3 + Conchiolin)

Amber (Resinite (Succinite if from the Baltic); Chemical Formula: C10H16O (approximate)) — Organic Diamond/Gemstone (often associated with Sedimentary sequences)

Amber

Resinite (Succinite if from the Baltic); Chemical Formula: C10H16O (approximate)

Organic Diamond/Gemstone (often associated with Sedimentary sequences)

Amber (Succinite (specific to Baltic amber), fossilized tree resin) — mineraloid

Amber

Succinite (specific to Baltic amber), fossilized tree resin

Chert (Iron-stained) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Iron-stained)

Chert (Silicon Dioxide, SiO2)

Sandstone Concretion (Clastic sedimentary rock (primarily Quartz SiO2)) — sedimentary

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

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

Fossiliferous Limestone

Calcite-rich Sedimentary Rock (CaCO3)

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

Pearl (Biogenic Mineral)

Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3

Chert (Light Grey / Flint variant) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Light Grey / Flint variant)

Cryptocrystalline Quartz (SiO2)

Chert (specifically Flint or Common Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Common Chert)

Silicon Dioxide (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Cherty Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert / Flint (Chert (SiO2)) — sedimentary

Chert / Flint

Chert (SiO2)

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

Chert (Iron-Stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Brecciated River Cobble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Brecciated River Cobble)

Silicon Dioxide (SiO2)

Tufa (Limestone) (Calcareous Tufa (CaCO3)) — sedimentary

Tufa (Limestone)

Calcareous Tufa (CaCO3)

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

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Chert (Field Stone) (Chert (SiO2)) — sedimentary

Chert (Field Stone)

Chert (SiO2)

Tree Agate (Dendritic Agate (Silicon Dioxide, SiO2)) — mineral

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

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

Chert (Jasper/Mudstone)

Silicon Dioxide (SiO2)

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

Chert (Chert Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (White-Tan variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White-Tan variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossiliferous Limestone with Rugose Coral (Calcite (CaCO3) matrix containing Rugosa (order of extinct solitary and colonial corals)) — sedimentary

Fossiliferous Limestone with Rugose Coral

Calcite (CaCO3) matrix containing Rugosa (order of extinct solitary and colonial corals)