Sapphire (Corundum)
Corundum (Al2O3)
mineral
Category
Metamorphic (Altered Igneous Rock)
Browse metamorphic (altered igneous rock) specimens identified by the Rock Identifier community.
Amethyst
Amethyst (Silicon Dioxide - SiO2)
mineral
Greenschist (Greenstone)
Greenschist (Metamorphic rock containing chlorite, actinolite, and epidote)
metamorphic
Greenstone (Greenstone River Pebble)
Greenschist (metamorphosed mafic igneous rock)
metamorphic
Greenstone
Greenschist (metamorphosed mafic igneous rock)
metamorphic
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Quartz (specifically Milky or Clear Quartz)
Silicon Dioxide (SiO2)
mineral
Smoky Quartz
Silicon Dioxide (SiO2) with aluminum impurities
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartz (Milky/Smoky variety on matrix)
Silicon Dioxide (SiO2)
mineral
Clear Quartz Crystal
Silicon Dioxide (SiO2)
mineral
Gneiss with Quartz Veining
Gneiss (High-grade regional metamorphic rock)
metamorphic
Greenstone (Greenschist)
Greenschist facies rock (containing chlorite, actinolite, and epidote)
metamorphic
Gneiss (Banded Gneiss)
Gneiss
metamorphic
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Greenschist
Greenschist facies rock (containing chlorite, actinolite, and epidote)
metamorphic
Banded Gneiss
Foliated Gneiss
metamorphic
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Gneiss
High-grade regional metamorphic rock (Foliated)
metamorphic
Gneiss (Metamorphic Cobble)
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Pink Granite Gneiss
Granitic Gneiss
metamorphic
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Limonite-stained Quartz
Silicon Dioxide (SiO2) with Iron Oxide/Hydroxide (FeO(OH)·nH2O) staining
mineral
Gneiss
Gneiss
metamorphic
Gneiss
High-grade foliated metamorphic rock
metamorphic
Peacock Ore (Bornite or Chalcopyrite treated with acid)
Bornite (Cu5FeS4) or Acid-washed Chalcopyrite (CuFeS2)
mineral
River Cobble (Salt and Pepper Gneiss)
Gneiss (High-grade regional metamorphic rock)
metamorphic
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Gneiss
Gneiss
metamorphic
Granite / Gneiss Complex
Felsic Plutonic Rock (Granite) or High-grade Metamorphic Rock (Gneiss)
igneous/metamorphic
Gneiss (Cobble)
Gneiss
metamorphic
Green Schist
Greenschist (composed of Chlorite, Actinolite, and Epidote)
metamorphic
Banded Gneiss
Gneiss (quartz-feldspar-biotite metamorphic rock)
metamorphic
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Smoky Quartz (Tumbled)
Smoky Quartz (SiO2 - Silicon Dioxide)
mineral
Quartz (Citrine or Iron-Stained variety)
Silicon Dioxide (SiO2)
mineral
Quartz (Smoky Quartz variant)
Silicon Dioxide (SiO2)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Gneiss (specifically a weathered Amphibolite or Garnet Gneiss)
Gneiss (complex silicate composition)
metamorphic