Carnelian Agate
Chalcedony (SiO2) with iron oxide inclusions
Category
Browse igneous or sedimentary specimens identified by the Rock Identifier community.
Carnelian Agate
Chalcedony (SiO2) with iron oxide inclusions
Chalcedony (Dyed Agate and Citrine-style Quartz)
Silicon Dioxide (SiO2)
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Quartz (Citrine or Iron-Stained variety)
Silicon Dioxide (SiO2)
Chalcedony (Common Agate)
Silicon Dioxide (SiO2)
Gneiss (with Quartzite and Mica)
Gneiss
Jasper
Silicon dioxide (SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Gneiss
Gneiss
Rough Precious Opal
Hydrated Silica (SiO2·nH2O)
Banded gneiss pebble
Gneiss, composed chiefly of quartz, feldspar, and mica/amphibole
Gneiss
Gneiss (High-grade Metamorphic Rock)
Gneiss (Banded Gneiss)
Gneiss
Banded metamorphic rock, likely gneiss
Biotite–quartz–feldspar gneiss, possibly migmatitic
Gneiss
Gneiss (Metamorphic Rock)
Gneiss
Gneiss
Gneiss
Gneiss (High-grade metamorphic rock)
Gneiss (with Quartzite layers)
Gneissic Metamorphic Rock
Gneiss (Pebble)
Gneiss
Banded gneiss (likely amphibolite-bearing gneiss)
Gneiss; quartz–feldspar–mica/amphibole aggregate
Gneiss with Quartz/Feldspar Vein
Quartz-Feldspathic Gneiss
Gneiss
Gneiss
Garnet Amphibolite (or Garnet Gneiss)
Garnet amphibolite / Garnet-bearing metamorphic rock
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Banded gneiss pebble
Gneiss, commonly quartz–feldspar–mica gneiss
Foliated metamorphic rock, likely gneiss with amphibolite or chlorite-rich bands
Biotite–quartz–feldspar gneiss, locally mafic amphibolite; mineral composition is uncertain from the photograph
Gneiss
High-grade foliated metamorphic rock
Banded Gneiss
Gneiss (High-grade metamorphic rock)
Gneiss (Metamorphic Rock)
Gneiss
Weathered iron-rich rock, possibly limonite-bearing basalt or ironstone
Undetermined; likely iron oxides/hydroxides (goethite–hematite–limonite) in a silicate host
Botryoidal Agate
Chalcedony (Silicon Dioxide, SiO2)
Clear Quartz Geode
Crystalline Silicon Dioxide (SiO2)
Banded Gneiss
Banded Orthogneiss or Paragneiss (Quartz-Feldspathic Gneiss)
Gneissic River Pebble
Gneiss
Chalcedony (Agate)
Cryptocrystalline Quartz (SiO2)
Red Agate
Chalcedony (SiO2)
Quartz (Clear Quartz)
Silicon Dioxide (SiO2)
Auriferous Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Yellow Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
Pyrite
Iron Disulfide (FeS2)
Banded gneiss
Gneiss, commonly quartz–feldspar–mica assemblage
Quartz–feldspar–mica metamorphic rock, likely gneiss
Gneiss; composition commonly quartz (SiO₂), feldspars, biotite/hornblende, and minor accessory minerals