Mica schist
Schist dominated by muscovite/biotite mica, commonly with quartz and feldspar
Category
Browse mineral (evaporite) specimens identified by the Rock Identifier community.
Mica schist
Schist dominated by muscovite/biotite mica, commonly with quartz and feldspar
Gneiss (likely biotite–quartz–feldspar gneiss)
Foliated gneiss; primarily quartz (SiO₂), feldspar, and biotite mica
Hag Stone
Perforated sedimentary rock (typically sandstone or limestone)
Granite
Intrusive igneous rock
Fossil / Permineralized Bone
Tyrannosaurus rex fossil (Hydroxylapatite replaced by various minerals)
Weathered basalt pebble
Basalt, a fine-grained mafic volcanic rock; likely containing plagioclase and pyroxene with weathering products
Quartz Geode or Nodular Quartz
Silicon Dioxide (SiO2) in Host Matrix
Yellow Apatite
Fluorapatite (Ca5(PO4)3(F,Cl,OH))
Hematite (likely Botryoidal or Specularite variant)
Iron(III) oxide (Fe2O3)
Hematite
Iron(III) oxide (Fe2O3)
Hematite
Hematite (Iron(III) oxide, Fe2O3)
Native Copper Nugget
Native Copper (Cu)
Geode (Calcite or Quartz)
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)
Sandstone
Arenite
Blue Chalcedony
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Limonite
FeO(OH)·nH2O
Sandstone with Quartz/Calcite druse
Arenite with druse (SiO2 or CaCO3)
Peacock Ore
Bornite (Cu5FeS4) or iridescent Chalcopyrite (CuFeS2)
Limonite
FeO(OH)·nH2O
Limonite
FeO(OH)·nH2O
Polished serpentine pebble
Serpentinite, chiefly serpentine-group minerals (chrysotile, lizardite, antigorite)
Unidentified metallic mineral or meteorite fragment
Indeterminate; possible native metal-bearing sulfide or iron meteorite fragment
Granite
Phaneritic intrusive igneous rock (Quartz, Feldspar, Mica)
Pink Granite (Unakite-bearing or Epidote-bearing Granite)
Plutonic Igneous Rock (Granite)
Gneiss
Gneiss (High-grade metamorphic rock)
Gneiss
Gneiss
Banded sandstone pebble
Quartz-rich lithic sandstone; exact provenance and composition require testing
Gneiss
Gneiss
Diorite (Salt and Pepper Rock)
Diorite
Gneiss
Gneiss
Concrete with Aggregate
Artificial Conglomerate (Cement and Aggregate)
Gneiss (Banded Gneiss)
Gneiss
Quartz-rich pegmatite with mica
Granitic pegmatite; mainly quartz (SiO₂), feldspar, and muscovite/biotite mica, with possible sulfide or iron-oxide staining
Diorite
Diorite (Phaneritic intermediate plutonic rock)
Diorite
Diorite (Intermediate intrusive igneous rock)
Gneiss
Gneiss (Metamorphic Rock)
Gneiss (Metamorphic Pebble)
Gneiss (SiO2-rich metamorphic rock)
Gneiss
Gneiss
Granite
Granite (Felsic Plutonic Rock)
Granodiorite
Granodiorite
Gneiss (foliated metamorphic rock)
Gneiss