Quartz on Sandstone
Silicon Dioxide (SiO2) in Lithic Sandstone
sedimentary
Category
Sedimentary Or Metamorphic (Low Grade)
Browse sedimentary or metamorphic (low grade) specimens identified by the Rock Identifier community.
Learn about Sedimentary Or Metamorphic (Low Grade) in the encyclopedia
View all →
Serpentinite
Serpentinite (composed primarily of serpentine group minerals like lizardite, chrysotile, or antigorite; Mg3Si2O5(OH)4)
metamorphic
Black Diamond / Black Sapphire
Carbon (C) or Corundum (Al2O3)
mineral
Coal
Coal (Sedimentary Rock / Organic Rock)
sedimentary
Serpentinite
Serpentinite (Mg, Fe, Ni)₃Si₂O―(OH)₄
metamorphic
Serpentine
Serpentinite (group of minerals: (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
metamorphic
Green Aventurine
Aventurine (Silicon dioxide, SiO₂)
Mineral; variety of Quartz
Orange Calcite (Mexican Onyx)
Calcium Carbonate (CaCO3)
mineral
Marble
Recrystallized Calcite (CaCO3) Rock
metamorphic
Raw Sapphire (Corundum)
Aluminum oxide (Al2O3)
gemstone
Rough Diamond
Diamond (Pure Carbon: C)
mineral
Rough Diamond
Diamond (C)
mineral
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium) CuAl6(PO4)4(OH)8·4H2O
mineral
Banded sandstone pebble
Lithic or quartz-rich sandstone; exact composition requires testing
sedimentary
Probable serpentinite (serpentine-rich rock)
Serpentinite; chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄), with possible magnetite and olivine remnants
metamorphic
Polished onyx marble (banded calcite)
Calcite, CaCO₃; commonly called Mexican onyx or cave onyx
metamorphic
Noble Serpentine
Antigorite (Mg3Si2O5(OH)4)
metamorphic
Jadeite Jade
NaAlSi2O6 (Sodium Aluminum Silicate)
gemstone
Anthracite
Anthracite (Carbon-rich metamorphic coal)
metamorphic
Green Fluorite
Calcium Fluoride (CaF2)
mineral
Amazonite
Microcline Feldspar (KAlSi3O8)
mineral
Black-and-white gneiss
Gneiss, chiefly quartz–feldspar with dark biotite/amphibole bands
metamorphic
Muscovite
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Epidote
{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
mineral
Yellow Sapphire
Corundum (Al2O3) with iron impurities
mineral
Tumbled dark green stone, likely serpentine
Serpentinite; chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄)
metamorphic
Shale
Mudrock / Fissile Shale
sedimentary
Ruby in Zoisite
Ruby (α-Al2O3) embedded in Zoisite (Ca2Al3(SiO4)3(OH)) with some Hornblende
Metamorphic Rock (composed of multiple minerals)
Shale
Shale (claystone/mudstone)
sedimentary
Quartz with Mica (Schist/Pegmatite fragment)
Silicon Dioxide (SiO2) with Phyllosilicates (KAl2(AlSi3O10)(OH)2)
igneous/metamorphic
Polished blue-green stone, likely serpentine or chrysocolla-bearing rock
Serpentine-group minerals, chiefly Mg₃Si₂O₅(OH)₄; exact identification requires testing
metamorphic
Serpentinite (likely)
Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, or chrysotile)
metamorphic
Weathered serpentinite (likely serpentine-rich rock)
Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with possible magnetite and accessory minerals
metamorphic
Potassium Feldspar (Orthoclase / Microcline)
KAlSi3O8
mineral
Tumbled serpentine
Serpentinite; chiefly serpentine-group minerals, Mg3Si2O5(OH)4
metamorphic
Shale
Shale (Fine-grained clastic sedimentary rock)
sedimentary
Tiger's Eye
Pseudomorph of quartz after crocidolite (SiO2 with iron inclusions)
metamorphic
Purple Garnet
Magnesium Aluminum Silicate (Pyrope-Almandine series) Mg3Al2(SiO4)3
gemstone
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Bornite
Copper Iron Sulfide (Cu5FeS4)
mineral
Tiger's Eye (Mineral Collection)
Tiger's Eye (SiO2 with crocidolite inclusions)
mineral
Pink Feldspar
Orthoclase (KAlSi3O8) or Microcline
mineral