Rock Identifier

Category

Basalt

Browse basalt specimens identified by the Rock Identifier community.

White Agate (resembling Bone Chalcedony) (Cryptocrystalline Quartz (SiO2)) — mineral

White Agate (resembling Bone Chalcedony)

Cryptocrystalline Quartz (SiO2)

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

Amethyst

Amethyst (SiO2 with iron impurities)

Sunstone (Plagioclase Feldspar (containing (Ca,Na)(Al,Si)4O8 with Hematite or Copper inclusions)) — mineral

Sunstone

Plagioclase Feldspar (containing (Ca,Na)(Al,Si)4O8 with Hematite or Copper inclusions)

Amethyst (Amethyst (Silicon Dioxide - SiO2 with Iron impurities)) — mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2 with Iron impurities)

Amethyst (Silicon Dioxide (SiO2) with traces of Iron (Fe3+)) — mineral

Amethyst

Silicon Dioxide (SiO2) with traces of Iron (Fe3+)

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

Amethyst (Faceted Gemstone)

Silicon Dioxide (SiO2) with iron impurities

Amethyst Geode (Amethyst (Silicon Dioxide), Formula: SiO2) — mineral

Amethyst Geode

Amethyst (Silicon Dioxide), Formula: SiO2

Amethyst (Amethyst (Silicon Dioxide SiO2 + Fe4+)) — mineral

Amethyst

Amethyst (Silicon Dioxide SiO2 + Fe4+)

Sunstone (Plagioclase Feldspar (Na,Ca)(Al,Si)4O8) — Mineral

Sunstone

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

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

Amethyst (Purple Quartz)

Silicon Dioxide (SiO2) with iron impurities

Limonitic Scoria (Vesicular Basalt with Iron Staining) (Highly vesicular basalt heavily stained by Limonite [FeO(OH)·nH2O]) — igneous

Limonitic Scoria (Vesicular Basalt with Iron Staining)

Highly vesicular basalt heavily stained by Limonite [FeO(OH)·nH2O]

Native Copper (Native Copper (Cu)) — mineral

Native Copper

Native Copper (Cu)

Amethyst (Amethyst (Purple Quartz); formula: SiO2 (Silicon Dioxide)) — mineral

Amethyst

Amethyst (Purple Quartz); formula: SiO2 (Silicon Dioxide)

Olivine (often within Peridotite) (Magnesium iron silicate, (Mg,Fe)2SiO4) — mineral

Olivine (often within Peridotite)

Magnesium iron silicate, (Mg,Fe)2SiO4

Carnelian (Carnelian Chalcedony (SiO2)) — mineral

Carnelian

Carnelian Chalcedony (SiO2)

Banded Agate (specifically Lake Superior Agate) (Silicon dioxide (SiO2) - Cryptocrystalline Chalcedony) — mineral

Banded Agate (specifically Lake Superior Agate)

Silicon dioxide (SiO2) - Cryptocrystalline Chalcedony

Amethyst (Amethyst (Silicon Dioxide, SiO2)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Greenstone (Protolith of basalt, diabase, or gabbro; often contains minerals like chlorite, actinolite, and epidote) — metamorphic

Greenstone

Protolith of basalt, diabase, or gabbro; often contains minerals like chlorite, actinolite, and epidote

Greenstone with Quartz Veining (Epidiorite or Metabasalt with SiO2 (Quartz) veins) — metamorphic

Greenstone with Quartz Veining

Epidiorite or Metabasalt with SiO2 (Quartz) veins

Prehnite (Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate hydroxide)) — mineral

Prehnite

Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate hydroxide)

Agate (specifically a Thunderegg/Agate Nodule) (Cryptocrystalline Quartz (SiO2)) — mineral

Agate (specifically a Thunderegg/Agate Nodule)

Cryptocrystalline Quartz (SiO2)

Greenschist (Chlorite Schist) (Greenschist (Metamorphic rock dominated by chlorite, actinolite, and epidote)) — metamorphic

Greenschist (Chlorite Schist)

Greenschist (Metamorphic rock dominated by chlorite, actinolite, and epidote)

Bauxite (Laterite Clay) (Bauxite (mixture of Hydrous Aluminum Oxides: Gibbsite Al(OH)3, Boehmite and Diaspore AlO(OH))) — sedimentary

Bauxite (Laterite Clay)

Bauxite (mixture of Hydrous Aluminum Oxides: Gibbsite Al(OH)3, Boehmite and Diaspore AlO(OH))

Dyed Blue Agate (Cryptocrystalline Quartz (SiO2)) — mineral

Dyed Blue Agate

Cryptocrystalline Quartz (SiO2)

Labradorite (Labradorite (a calcium-enriched sodic plagioclase feldspar mineral - (Ca, Na)(Al, Si)4O8)) — mineral

Labradorite

Labradorite (a calcium-enriched sodic plagioclase feldspar mineral - (Ca, Na)(Al, Si)4O8)

Prehnite (Prehnite (Ca2Al2Si3O10(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al2Si3O10(OH)2)

Greenstone (Greenschist (metamorphosed mafic igneous rock)) — metamorphic

Greenstone

Greenschist (metamorphosed mafic igneous rock)

Banded Agate (Chalcedony (Silicon Dioxide, SiO2)) — mineral

Banded Agate

Chalcedony (Silicon Dioxide, SiO2)

Pink Amethyst Geode (Silicon Dioxide (SiO2) with Hematite/Iron impurities) — mineral

Pink Amethyst Geode

Silicon Dioxide (SiO2) with Hematite/Iron impurities

Thunderegg (Agetized Geode nodule) (Rhyolitic Agate Nodule (SiO2 filling volcanic cavities)) — igneous

Thunderegg (Agetized Geode nodule)

Rhyolitic Agate Nodule (SiO2 filling volcanic cavities)

Amygdaloidal Basalt with Quartz/Zeolite Infill (Amygdaloidal Basalt (extrusive volcanic rock with SiO2 or CaAl2Si3O10·3H2O infill)) — igneous

Amygdaloidal Basalt with Quartz/Zeolite Infill

Amygdaloidal Basalt (extrusive volcanic rock with SiO2 or CaAl2Si3O10·3H2O infill)

Carnelian (Carnelian (Microcrystalline Quartz, SiO2 with Fe2O3 impurities)) — mineral

Carnelian

Carnelian (Microcrystalline Quartz, SiO2 with Fe2O3 impurities)

Flower Agate (Chalcedony with Opaque Spherulitic Inclusions (SiO2)) — Mineral

Flower Agate

Chalcedony with Opaque Spherulitic Inclusions (SiO2)

Carnelian Agate (Silicon Dioxide (SiO2) with Iron Oxide impurities) — mineral

Carnelian Agate

Silicon Dioxide (SiO2) with Iron Oxide impurities

Olivine (Peridotite) (Magnesium Iron Silicate - (Mg, Fe)2SiO4) — igneous

Olivine (Peridotite)

Magnesium Iron Silicate - (Mg, Fe)2SiO4

Peridotite (Olivine) (Peridotite (comprising (Mg,Fe)2SiO4)) — igneous

Peridotite (Olivine)

Peridotite (comprising (Mg,Fe)2SiO4)

Peridot (Olivine) (Magnesium Iron Silicate (Mg,Fe)2SiO4) — mineral

Peridot (Olivine)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Carnelian (Chalcedony) (Silicon Dioxide (SiO2) with Iron Oxide impurities) — mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2) with Iron Oxide impurities

Vesicular Basalt with Oxidation (Scoriaceous Olivine Basalt (Mafic volcanic rock)) — igneous

Vesicular Basalt with Oxidation

Scoriaceous Olivine Basalt (Mafic volcanic rock)

Greenstone (Greenschist (containing chlorite, epidote, and actinolite)) — metamorphic

Greenstone

Greenschist (containing chlorite, epidote, and actinolite)

Banded Agate Geode (Silicon Dioxide (SiO2)) — mineral

Banded Agate Geode

Silicon Dioxide (SiO2)

Amethyst and Citrine (Ametrine Mix) (Silicon Dioxide (SiO2) with Fe3+ impurities) — mineral

Amethyst and Citrine (Ametrine Mix)

Silicon Dioxide (SiO2) with Fe3+ impurities