Mica
Phlogopite or Biotite group (KMg3(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)
Category
Browse metamorphic (altered igneous rock) specimens identified by the Rock Identifier community.
Mica
Phlogopite or Biotite group (KMg3(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)
Wishing Stone with Quartz Veins
Quartzite or Quartz-veined Metamorphic Rock (composed mainly of SiO2)
Granite
Granite
Graphite
Graphite (C)
Unakite
Epidotized Granite
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Granodiorite
Granodiorite (Intermediate intrusive igneous rock)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Quartz (Rock Crystal)
Quartz (SiO₂ - Silicon Dioxide)
Pegmatite (likely Granitic Pegmatite)
Pegmatite (a coarse-grained igneous rock, often with granitic composition)
Epidote in Quartz
Quartz with Epidote inclusions (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH) inclusions)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Quartz vein in metamorphic rock
Crystalline Silicon Dioxide (SiO2) in Host Rock
Yellow Quartzite (River Pebble)
Quartzite (primarily Silicon Dioxide, SiO2)
Glacial Cobbles (predominantly Granite and Gneiss)
Mixed lithologies (Quartz, Feldspar, Mica assemblage)
Quartzite Pebble
Metamorphic Quartzite (SiO2)
Porphyritic Andesite/Basalt or Diorite River Rock
Porphyritic Igneous Rock
Banded Gneiss
Gneiss (pronounced "nice")
Unakite
Unakite (Epidotized Granite)
Quartzite
Quartzite (primarily SiO2)
Basalt
Basalt
Chalcopyrite
Copper Iron Sulfide (CuFeS2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Magnetic Sand Grain / Magnetite Pellet
Magnetite (Fe3O4)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8)
Citrine
Silicon dioxide (SiO2)
Quartz (Smoky/Milky variety)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz
Quartz (SiO₂)
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
Labradorite
Labradorite (a variety of Plagioclase Feldspar), Na(AlSi3O8) to Ca(Al2Si2O8)
Quartz
Quartz (SiO₂)
Pyrite in Matrix (Gold-colored Chalcopyrite or Pyrite)
Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)
Spessartine Garnet
Manganese aluminum silicate (Mn2+3Al2(SiO4)3)
Banded Slate or Siltstone with Quartz/Calcite Veins
Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)
Agate
Agate (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)