Rock Identifier

Category

Organic (Geological Relative)

Browse organic (geological relative) specimens identified by the Rock Identifier community.

Basalt (Basalt (extrusive volcanic rock)) — igneous

Basalt

Basalt (extrusive volcanic rock)

Basalt with Calcite Veins (Basalt (containing CaCO3 inclusions)) — igneous

Basalt with Calcite Veins

Basalt (containing CaCO3 inclusions)

Serpentine, likely a variety of Chrysoprase (green chalcedony) or a similar translucent green mineral. (Serpentine Group Minerals (e.g., Antigorite, Lizardite) or Chalcedony (SiO2) with nickel impurities for Chrysoprase green.) — mineral

Serpentine, likely a variety of Chrysoprase (green chalcedony) or a similar translucent green mineral.

Serpentine Group Minerals (e.g., Antigorite, Lizardite) or Chalcedony (SiO2) with nickel impurities for Chrysoprase green.

Basalt (Extrusive Igneous Rock (Mafic)) — igneous

Basalt

Extrusive Igneous Rock (Mafic)

Limestone (or Calcite Pebble) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (or Calcite Pebble)

Calcium Carbonate (CaCO3)

Chert (Chert (SiO2)) — sedimentary

Chert

Chert (SiO2)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Chert Pebble (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble

Microcrystalline Quartz (SiO2)

Banded Chert (Silicon Dioxide (SiO2)) — sedimentary

Banded Chert

Silicon Dioxide (SiO2)

Basalt (Vesicular and Scoria) (Basalt (extrusive volcanic rock)) — igneous

Basalt (Vesicular and Scoria)

Basalt (extrusive volcanic rock)

Mother of Pearl and Onyx (Aragonite (Mother of Pearl) and Chalcedony (Onyx)) — mineral

Mother of Pearl and Onyx

Aragonite (Mother of Pearl) and Chalcedony (Onyx)

Polished copper-bearing rock, likely cuprite-rich copper ore (Cuprite (Cu₂O) with native copper and iron-oxide matrix, probable) — mineral

Polished copper-bearing rock, likely cuprite-rich copper ore

Cuprite (Cu₂O) with native copper and iron-oxide matrix, probable

Tumbled turquoise-like stone (Likely turquoise, hydrated copper aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O) — mineral

Tumbled turquoise-like stone

Likely turquoise, hydrated copper aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O

Marble (Metamorphosed Limestone (principally CaCO3)) — metamorphic

Marble

Metamorphosed Limestone (principally CaCO3)

Basalt (Basalt (Aphanitic Mafic Volcanic Rock)) — igneous

Basalt

Basalt (Aphanitic Mafic Volcanic Rock)

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Chert Pebble (Chert (SiO2)) — sedimentary

Chert Pebble

Chert (SiO2)

Quartz-veined Limestone (Sedimentary limestone with quartz/calcite veinlets) — sedimentary

Quartz-veined Limestone

Sedimentary limestone with quartz/calcite veinlets

Basalt (Basalt (Aphanitic Mafic Igneous)) — igneous

Basalt

Basalt (Aphanitic Mafic Igneous)

Blue calcite (Calcite (calcium carbonate, CaCO₃)) — mineral

Blue calcite

Calcite (calcium carbonate, CaCO₃)

Lava Rock (Scoria) (Scoria (Mafic volcanic rock)) — igneous

Lava Rock (Scoria)

Scoria (Mafic volcanic rock)

Tufa (Vesicular Limestone) (Tufa (form of Calcium Carbonate, CaCO3)) — sedimentary

Tufa (Vesicular Limestone)

Tufa (form of Calcium Carbonate, CaCO3)

Basalt (Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)) — igneous

Basalt

Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)

Peridotite (Ultramafic intrusive igneous rock) — igneous

Peridotite

Ultramafic intrusive igneous rock

Basalt (Extrusive Igneous Rock) — igneous

Basalt

Extrusive Igneous Rock

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Basalt (Basalt (containing mainly Plagioclase feldspar and Pyroxene)) — igneous

Basalt

Basalt (containing mainly Plagioclase feldspar and Pyroxene)

Bog Iron / Limonite Concretion (Goethite/Limonite mixture (FeO(OH)·nH2O)) — sedimentary

Bog Iron / Limonite Concretion

Goethite/Limonite mixture (FeO(OH)·nH2O)

Vesicular Basalt / Scoria (with Iron Oxide Alteration) (Vesicular Basalt) — igneous

Vesicular Basalt / Scoria (with Iron Oxide Alteration)

Vesicular Basalt

Ironstone Concretion / Goethite Nodules (Ironstone (composed primarily of Goethite FeO(OH) and Limonite)) — sedimentary

Ironstone Concretion / Goethite Nodules

Ironstone (composed primarily of Goethite FeO(OH) and Limonite)

Gneiss (Gneiss (High-grade metamorphic rock)) — metamorphic

Gneiss

Gneiss (High-grade metamorphic rock)

Pearls (likely freshwater cultured pearls) (Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin) — gemstone

Pearls (likely freshwater cultured pearls)

Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin

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

Chert (Flint)

Silicon Dioxide (SiO2)

Desert Rose Fragment (Atypical) / Weathered Chert (Silicon Dioxide (SiO2) or Barium Sulfate (BaSO4) depending on exact mineralogy) — sedimentary

Desert Rose Fragment (Atypical) / Weathered Chert

Silicon Dioxide (SiO2) or Barium Sulfate (BaSO4) depending on exact mineralogy

Pumice (Vesicular Rhyolite or Andesite (Amorphous volcanic glass)) — igneous

Pumice

Vesicular Rhyolite or Andesite (Amorphous volcanic glass)

Black Freshwater Pearls (Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3) — mineral

Black Freshwater Pearls

Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Chert (Jasper variation) (Chert (Microcrystalline Silicon Dioxide, SiO2)) — sedimentary

Chert (Jasper variation)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Basalt (Mafic Volcanic Rock) — igneous

Basalt

Mafic Volcanic Rock

Green Onyx (Carved Mushroom) (Calcite / Banded Calcite (often commercially sold as 'Mexican Onyx')) — sedimentary

Green Onyx (Carved Mushroom)

Calcite / Banded Calcite (often commercially sold as 'Mexican Onyx')

Basalt (Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)) — igneous

Basalt

Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)