Sapphire
Corundum (Al2O3)
Category
Browse metamorphic rock specimens identified by the Rock Identifier community.
Sapphire
Corundum (Al2O3)
Gneiss (with iron staining)
Gneiss
Clear Quartz
Silicon Dioxide (SiO2) / Rock Crystal
Quartz in Matrix (possibly with Biotite or Hornblende)
Quartz (Silicon Dioxide, SiO2) in Granitic Matrix
Quartzite
Quartzite (primarily SiO2)
Quartz (Water-worn pebble)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartzite Pebble
Quartzite (composed primarily of SiO2)
Red Tiger's Eye
Silicified Crocidolite (Quartz pseudo-morph after Crocidolite), SiO2
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3Si2O5(OH)4
Quartzite River Rock (with iron staining)
Metamorphosed Sandstone (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Quartz (likely a form of massive or vein quartz)
Quartz (SiO₂)
Limonite (Iron Ore)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
Amethyst
SiO2 (Silicon Dioxide with Iron impurities and natural radiation influence)
Quartz (Milky or Common Quartz)
Silicon Dioxide (SiO2)
Mica Schist
Mica Schist
Quartzite (likely Iron-stained)
SiO2 (Metamorphosed Sandstone)
Marble
Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)
Quartz Vein in Matrix
Silicon Dioxide (SiO2)
Schist
Mica Schist (formula variable based on mineral content, typically containing [K,Al,Fe,Mg,Si,O,H])
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
Serpentinite
Serpentinite (composed primarily of serpentine group minerals like lizardite, antigorite, and chrysotile)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Quartzite (Beach Pebble)
Quartzite (composed primarily of SiO2)
Thulite in Matrix
Pink Zoisite - Ca2Al3(SiO4)3(OH)
Quartz (in a rock matrix)
Quartz (SiO2)
Granitoid (Granite/Gneiss mix)
Phaneritic Felsic Igneous Rock
Schist
Mica Schist
Gold Ore in Quartz
Native Gold (Au) in Quartz (SiO2)
Gneiss (Banded Gneiss)
Gneiss
Gneiss
Gneiss
Peacock Ore (Bornite or Chalcopyrite treated with acid)
Bornite (Cu5FeS4) or Acid-washed Chalcopyrite (CuFeS2)
River Stone (Quartzite/Chert)
Metamorphosed Quartz-rich Sedimentary Rock
Pink Quartzite
Quartzite (primarily SiO2 with trace impurities of iron oxides)
Quartzite
Quartzite
Gneiss (specifically a Granitic Gneiss)
Gneiss (Composition: Quartz, Feldspar, Mica)
Nuummite
Nuummite (Ortho-amphibole rock, primarily Anthophyllite and Gedrite)