Black Tourmaline
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
mineral
Category
Metamorphic (Likely Gneiss Or Schist Based On Texture)
Browse metamorphic (likely gneiss or schist based on texture) specimens identified by the Rock Identifier community.
Learn about Metamorphic (Likely Gneiss Or Schist Based On Texture) in the encyclopedia
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Ruby
Corundum (Al2O3 with Chromium impurities)
mineral
Dyed Agate Slice
Chalcedony (Silicon Dioxide, SiO2) with artificial pigment
mineral
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 cement)
sedimentary
Basalt (River Stone)
Basalt (SiO2 range 45-52%)
igneous
River Cobble (Phyllite or Quartzite)
Metasedimentary Rock (often containing SiO2 or KAl2(AlSi3O10)(OH)2)
metamorphic
River Cobbles (Quartzite and Sandstone)
Metamorphosed Quartz-rich Sedimentary Rock
metamorphic
Quartzite
Quartzite (chiefly SiO2)
metamorphic
Weathered quartz-rich rock, likely silicified limestone or quartzite
Microcrystalline quartz (SiO₂), possibly with calcite (CaCO₃) and iron-oxide staining
metamorphic
Shale with Quartz Veins
Fissile Sedimentary Rock (SiO2)
sedimentary
Mica Schist with Pyrite and Quartz
Metamorphic Rock (Muscovite-Biotite Schist)
metamorphic
Pyrite (on Quartz/Host Rock)
Iron Sulfide (FeS₂)
mineral
Crystalline limestone (marble-like calcite rock)
Calcite, CaCO₃; likely recrystallized limestone (marble)
metamorphic
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Green Aventurine
Aventurine Quartz (SiO2 + Fuchsite mica)
Mineral
Basalt (with possible weathered crust)
Basalt (composition: Plagioclase feldspar, Pyroxene, Olivine)
igneous
Mica Schist
Metamorphic rock dominated by mica minerals
metamorphic
Ruby in Fuchsite
Corundum (Al2O3) in Chrome-Mica (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
River Pebble (likely Quartzite or Chert)
Sedimentary Clast (Silicon Dioxide dominant)
sedimentary
Quartzite (with Quartz Veining)
Quartzite (SiO2)
metamorphic
Ferro-silicate Slag
Industrial Vitrified Slag (High-silica amorphous glass)
Mineral byproduct (Anthropogenic)
Quartzite
Quartzite (primarily SiO2)
metamorphic
Conglomerate
Clastic sedimentary rock (Conglomerate)
sedimentary
Gastropod Steinkern (Fossil Snail Internal Mold)
Class Gastropoda (Internal Mold)
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Sandstone (Graywacke type)
Clastic Sedimentary Rock (Lithic Sandstone)
sedimentary
Quartzite (or Iron-Stained Quartz Pebble)
Silicon Dioxide (SiO2) with Ferric Oxide inclusions
metamorphic
Quartzite pebble
Quartzite
metamorphic
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
mineral
K-Feldspar (Microcline / Orthoclase)
Potassium Feldspar (KAlSi3O8)
mineral
K-Feldspar (Microcline / Orthoclase)
Potassium Feldspar (KAlSi3O8)
mineral
Mica (specimen appears to be Muscovite or Phlogopite)
Phyllosilicate mineral; Muscovite: KAl2(AlSi3O10)(F,OH)2
Mineral (Found in Igneous and Metamorphic rocks)
Sandstone (Red)
Arenite (primarily Quartz, SiO2, with Iron Oxide cement)
sedimentary
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
gemstone
Quartz-rich metamorphic rock, possibly quartzite
Quartzite; primarily crystalline silicon dioxide (SiO₂), with minor feldspar, mica, or iron oxides
metamorphic
Garnet Schist
Almandine-bearing Mica Schist
metamorphic
Anthracite
Anthracite (highest-grade coal)
metamorphic
Schist with Quartz Vein
Mica Schist with SiO2 vein
metamorphic
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
mineral
Rough Green Tourmaline (Verdelite)
Elbaite (Complex Silicate) - Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
mineral
Ruby
Corundum (Aluminum Oxide with Chromium), Al2O3:Cr
mineral
Porphyritic Basalt (likely artificially dyed or altered)
Basalt with plagioclase phenocrysts (likely treated)
igneous