Rock Identifier

Category

Mineral, Organic Gemstone

Browse mineral, organic gemstone specimens identified by the Rock Identifier community.

Chert (Flint) (Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (Flint)

Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)

Chert (and Limestone) (Chert (consisting of Microcrystalline Quartz, SiO2)) — sedimentary

Chert (and Limestone)

Chert (consisting of Microcrystalline Quartz, SiO2)

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

Chert (variations include Flint/Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossil Coral (Favosites Honeycomb) (Favosites (Genus), Phylum Cnidaria, Class Anthozoa) — sedimentary

Fossil Coral (Favosites Honeycomb)

Favosites (Genus), Phylum Cnidaria, Class Anthozoa

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Greenstone / Chert (Cryptocrystalline Quartz (SiO2) or Altered Basalt) — sedimentary or metamorphic

Greenstone / Chert

Cryptocrystalline Quartz (SiO2) or Altered Basalt

sedimentary or metamorphic

Chert (specifically Banded Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Banded Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Septarian Nodule (Septarian Dragon Stone) (Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)) — sedimentary

Septarian Nodule (Septarian Dragon Stone)

Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)

Shale (Shale) — sedimentary

Shale

Shale

Sunstone (Aventurine Feldspar ((Ca,Na)(Al,Si)4O8)) — mineral

Sunstone

Aventurine Feldspar ((Ca,Na)(Al,Si)4O8)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Carnelian Agate (Silicon Dioxide (SiO2) with iron oxide impurities) — Mineral

Carnelian Agate

Silicon Dioxide (SiO2) with iron oxide impurities

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Variscite in Matrix (Variscite (AlPO4 · 2H2O)) — mineral

Variscite in Matrix

Variscite (AlPO4 · 2H2O)

Ironstone Concretion (Siderite or Hematite Concretion) — sedimentary

Ironstone Concretion

Siderite or Hematite Concretion

Moonstone (Orthoclase Feldspar (formula: (K,Na)AlSi3O8)) — mineral

Moonstone

Orthoclase Feldspar (formula: (K,Na)AlSi3O8)

Chrysocolla (with Quartz and Azurite) (Hydrated copper phyllosilicate mineral [Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)]) — mineral

Chrysocolla (with Quartz and Azurite)

Hydrated copper phyllosilicate mineral [Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)]

Amethyst (Quartz variety; SiO2 (Silicon Dioxide)) — Mineral

Amethyst

Quartz variety; SiO2 (Silicon Dioxide)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Howlite (Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)) — mineral

Howlite

Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)

Chert (Arrowhead Fragment) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead Fragment)

Microcrystalline Quartz (SiO2)

Chert (Flint nodule) (Silicon dioxide (SiO2)) — sedimentary

Chert (Flint nodule)

Silicon dioxide (SiO2)

Sphalerite in Matrix (Polished Point) (Zinc sulfide (Zn,Fe)S) — mineral

Sphalerite in Matrix (Polished Point)

Zinc sulfide (Zn,Fe)S

Prehnite (Prehnite (Ca2Al(AlSi3O10)(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Rhodochrosite (Manganese Carbonate (MnCO3)) — mineral

Rhodochrosite

Manganese Carbonate (MnCO3)

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Pearl (Calcium carbonate (CaCO3) - Aragonite/Calcite variety) — mineral

Pearl

Calcium carbonate (CaCO3) - Aragonite/Calcite variety

Citrine Quartz (Silicon Dioxide (SiO2) with iron impurities) — mineral

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Citrine (Silicon Dioxide (SiO2)) — mineral

Citrine

Silicon Dioxide (SiO2)

Chrysocolla (Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)) — mineral

Chrysocolla

Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)

Turquoise (CuAl6(PO4)4(OH)8·4H2O) — mineral

Turquoise

CuAl6(PO4)4(OH)8·4H2O

Amazonite in Pegmatite Matrix with Smoky Quartz (K(AlSi3O8) - Microcline (var. Amazonite) with SiO2 (Quartz)) — Mineral

Amazonite in Pegmatite Matrix with Smoky Quartz

K(AlSi3O8) - Microcline (var. Amazonite) with SiO2 (Quartz)

Moonstone (Orthoclase Feldspar ((K,Na)AlSi3O8)) — mineral

Moonstone

Orthoclase Feldspar ((K,Na)AlSi3O8)

Petrified Wood (Silicified Wood (primarily SiO2 - Silicon Dioxide)) — mineral

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Liesegang Ring Siltstone (Siltstone with iron oxide Liesegang bands) — sedimentary

Liesegang Ring Siltstone

Siltstone with iron oxide Liesegang bands

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Blue Agate (Tumbled and Dyed) (Silicon Dioxide (SiO2) with likely organic dyes) — mineral

Blue Agate (Tumbled and Dyed)

Silicon Dioxide (SiO2) with likely organic dyes

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)

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

Tiger's Eye

Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2