Graphite
Graphite (C)
Category
Browse metamorphic (pseudo igneous) specimens identified by the Rock Identifier community.
Graphite
Graphite (C)
White Jade (Nephrite)
Nephrite, Ca2(Mg,Fe)5Si8O22(OH)2
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Marble
Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within metamorphic/igneous matrix
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(OH)₄(BO₃)₃Si₆O₁₈)
Granitoid (Granite/Gneiss mix)
Phaneritic Felsic Igneous Rock
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
Pebble
Clast (specifically a granule or small pebble)
Diorite (Gneissic)
Diorite
Pink Granite (Gneissic transition)
Pink Biotite Granite
Milky Quartz
Silicon Dioxide (SiO2)
Aquamarine
Beryl (Be3Al2Si6O18)
Quartz Crystal
Quartz (SiO₂)
Quartz
Quartz (SiO₂)
Quartz
Quartz (Silicon Dioxide, SiO2)
Schist
Schist (various mineralogical compositions including mica, chlorite, talc, etc.)
Gneiss
Gneiss (Metamorphic rock of variable composition, typically SiO2 rich)
Citrine Quartz Crystal Cluster
Silicon Dioxide (SiO2) with iron impurities
Citrine
Citrine (Silicon Dioxide, SiO2)
Ruby
Corundum (Al2O3 with Chromium traces)
Ruby
Corundum (Aluminum Oxide with Chromium traces), Al2O3:Cr
Ruby
Corundum (Al2O3:Cr)
Sodalite
Na8(Al6Si6O24)Cl2 (Sodalite)
Milky Quartz
Silicon Dioxide (SiO2)
Water and Silt (Sedimentary Environment)
Suspended Sediment / H2O (dihydrogen monoxide)
Amethyst (Chevron or Banded Amethyst)
Silicon Dioxide (SiO2) with iron impurities
Red Garnet
Pyrope-Almandine series (Mg3Al2(SiO4)3 to Fe3Al2(SiO4)3)
Milky Quartz
Silicon Dioxide (SiO2)
Bull Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Black Tourmaline (Schorl)
NaFe3Al6(BO3)3Si6O18(OH)4
Milky Quartz with Iron Oxide Staining
Quartz (Silicon Dioxide, SiO2)
Smoky Quartz (Vein Quartz)
Quartz (Silicon Dioxide, SiO2)
White Quartz (Milky Quartz)
Quartz (Silicon Dioxide, SiO2)
Amethyst Quartz
Silicon Dioxide (SiO2)
Greenstone / Diabase Porphyry
Porphyritic Diabase (Micro-gabbro)
Baroque Pearl (and potentially a small Sapphire/Blue Topaz)
Pearl: Calcium Carbonate (aragonite or calcite) with conchiolin. Sapphire: Aluminum Oxide (Al2O3). Blue Topaz: Al2SiO4(F,OH)2.
Green Aventurine and Clear Quartz
Green Aventurine (Silicon Dioxide - SiO2 with Fuchsite inclusions); Clear Quartz (Silicon Dioxide - SiO2)
Gneiss (Metamorphic Rock)
Gneiss
Citrine
Citrine (Silicon Dioxide - SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Milky/Gravel variety)
Silicon Dioxide (SiO2)