Schist
Mica Schist (contains muscovite/biotite and quartz)
metamorphic
Category
Sedimentary Rock
Browse sedimentary rock specimens identified by the Rock Identifier community.
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Mineral
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Dark-colored Igneous Rock (likely Basalt or Diabase)
Basalt (extrusive igneous) or Diabase (intrusive igneous)
Igneous Rock
Milky Quartz (Quartz Vein)
Silicon Dioxide (SiO2)
mineral
River Cobble (Gneiss/Migmatite)
Gneissic Metamorphic Rock (composed mainly of Quartz, Feldspar, and Biotite)
metamorphic
River Cobble (likely Basalt or Chert)
Siliceous River Rock / Microcrystalline Quartz / Mafic Igneous
igneous/sedimentary
Quartz (pebble)
Quartz (SiO₂)
Mineral
Pumice
Pumice (Vesicular Rhyolite/Andesite)
igneous
Fluorite and Rose Quartz
Fluorite (CaF2), Rose Quartz (SiO2)
Mineral
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Unakite
Epidotized Granite
metamorphic
Pink Quartzite
Quartzite (SiO2 with minor iron oxide impurities)
metamorphic
Vesicular Basalt (or Scoria)
Vesicular Basalt (Aphanitic-vesicular volcanic rock)
igneous
Not a geological specimen
N/A (man-made object)
N/A
Quartzite
Quartzite (primarily SiO2)
metamorphic
Porphyry
Porphyritic Rock
igneous
Milky Quartz with Country Rock contact
Silicon Dioxide (SiO2) in contact with Metamorphic/Igneous rock
mineral
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral
Agate Geode
Silicon Dioxide (SiO2) - Chalcedony / Quartz Variety
Mineral
Vesicular Basalt
Basalt with vesicular texture
igneous
Yellow Quartzite
Quartzite (SiO2 with iron oxide inclusions)
metamorphic
Peridotite (Pyroxenite/Serpentinized Dunite)
Ultramafic Rock (consisting primarily of Olivine and Pyroxene)
igneous
Quartz
Quartz (SiO₂)
Mineral
Schist
Mica Schist (Medium-grade Metamorphic Rock)
Metamorphic
Glacial Cobble (likely Granitic or Gneissic)
Granite/Gneiss Glacial Erratic
igneous
Quartz (Milky/Crystalline)
Silicon Dioxide (SiO2)
mineral
Chert (or Flint)
SiO2 (predominantly microcrystalline quartz)
Sedimentary
Gneiss (specifically a Granitic Gneiss specimen)
Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)
metamorphic
Banded Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica)
metamorphic
White Topaz
Aluminum Silicate Fluoride Hydroxide; Al2SiO4(F,OH)2
mineral
Granite
Phaneritic Plutonic Igneous Rock (primarily composed of quartz, alkali feldspar, and plagioclase)
igneous
Quartz (likely a clear or rock crystal variety)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Jasper (Milky/Cream Variety)
Silicon Dioxide (SiO2) - variety of Chalcedony
sedimentary (chemical/biological)
Banded Gneiss (Variety of Gneiss)
Gneiss (specifically, a variety exhibiting prominent banding; mineral composition can vary, but often contains quartz, feldspar, mica, and amphibole)
Metamorphic Rock
Amethyst
Silicon Dioxide (SiO2) with Iron impurities
mineral
Serpentine
Antigorite, Lizardite, or Chrysotile (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
metamorphic
Basalt with Calcite Veins
Basalt (Mafic Volcanic Rock)
igneous
Basalt
Basalt (Mafic volcanic rock)
igneous
Banded Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Biotite/Amphiboles)
metamorphic
Quartz-veined Basalt
Amygdaloidal or Porphyritic Basalt with Silicon Dioxide (SiO2) vein
igneous
Aquamarine and clear quartz
Aquamarine (Be3Al2Si6O18), Quartz (SiO2)
Mineral