Gneiss
Gneiss (foliated metamorphic rock)
metamorphic
Category
Metamorphic Rock (Composed Of Multiple Minerals)
Browse metamorphic rock (composed of multiple minerals) specimens identified by the Rock Identifier community.
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Banded gneiss pebble
Foliated gneiss, typically quartz–feldspar–mica bearing
metamorphic
Riverstone (Quartzite Pebble)
Quartzite (primarily SiO2)
metamorphic
Septarian Nodule
Septaria (composed of Calcite, Aragonite, and Limestone)
sedimentary
Serpentinite
Serpentinite (composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite)
metamorphic
Sandstone
Arenite (SiO2 + various cementing minerals)
sedimentary
Polished agate/jasper pebble (probable)
Microcrystalline quartz, SiO₂, with iron-oxide and other inclusions
mineral
Weathered granite or granitic rock fragment
Granite; chiefly quartz, feldspar, and mica/amphibole
igneous
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Sedimentary or Metamorphic (low grade)
Polished granite or gneiss stone
Granite, chiefly quartz, feldspar, and dark mica/amphibole; exact identification is uncertain from the photograph
igneous
Oolitic Limestone
Oolite (Sedimentary rock composed of CaCO3)
sedimentary
Granite (likely)
Granite, a quartz–feldspar–mica intrusive igneous rock
igneous
Granite (Giallo Ornamental / Venetian Gold)
Granite (composed mainly of Quartz, Feldspar, Biotite, and Garnet)
igneous
Quartzite
Quartzite (composed primarily of Silica, SiO2)
metamorphic
Quartzite
Quartzite (composed primarily of Quartz, SiO2)
metamorphic
Dalmation Jasper
Dalmation Stone (perthitic feldspar with arfvedsonite)
igneous
Granite
Granite (Plutonic Igneous Rock)
igneous
River Siltstone / Mudstone Pebble
Siltstone (composed of mixed silicate and carbonate minerals)
sedimentary
Fancy Jasper (Butterfly Carving)
Silicon Dioxide (SiO2) with iron and manganese inclusions
sedimentary
Soapstone (Talc Steatite) Carving
Steatite (Hydrous magnesium silicate, Mg3Si4O10(OH)2)
metamorphic
Gneiss (likely)
Gneiss
Metamorphic
Red Sandstone
Arenite (high iron oxide content)
sedimentary
Greenschist
Greenschist (composed mainly of actinolite/tremolite, chlorite, and epidote)
metamorphic
Weathered granitic rock (tentative)
Granite, composed mainly of quartz, feldspar, and mica
igneous
Red Sandstone (Iron-Rich)
Arenite (Fe2O3)
sedimentary
Biotite gneiss (probable)
Foliated gneiss composed mainly of quartz, feldspar, and biotite mica
metamorphic
Pebble
Clast (specifically a granule or small pebble)
Sedimentary
Diorite with Quartz Veins
Diorite
igneous
Dalmatian Stone
Dalmatian Jasper (a misnomer) / Perthitic Feldspar Rock
igneous
Granite
Phaneritic intrusive igneous rock
igneous
Fossil Shell
Invertebrate fossil (Mollusca)
fossil
Mica Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
metamorphic
Basalt
Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 with (Ca,Na)(Al,Si)4O8
igneous
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Polished tiger iron
Tiger iron: banded quartz–crocidolite/jasper–hematite rock
metamorphic
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
metamorphic
Granite
Granite
igneous
Schist
Schist
metamorphic
Basalt
Extrusive Igneous Rock
igneous
Marble
Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)
metamorphic
Bauxite
Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)
sedimentary
Lapis lazuli
Lapis lazuli; primarily lazurite (Na₃Ca(Si₃Al₃)O₁₂S), with calcite and pyrite
metamorphic