Black Tourmaline (Schorl)
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
mineral
Category
Metamorphic Rock (For Both Nephrite And Jadeite)
Browse metamorphic rock (for both nephrite and jadeite) specimens identified by the Rock Identifier community.
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Quartz pebble
Silicon dioxide (SiO2)
mineral
Black Tourmaline (Schorl)
Schorl (Sodium iron aluminum borosilicate hydroxide) NaFe3Al6(BO3)3Si6O18(OH)4
mineral
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Banded Quartzite Cobble
Quartzite (SiO2 with minor iron oxides)
metamorphic
Polished dark mineral fragments, likely hematite or magnetite
Hematite (Fe₂O₃) or magnetite (Fe₃O₄)
mineral
Sandstone (Quartzose type)
Arenite (primarily SiO2)
sedimentary
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Scoria
Vesicular Mafic Igneous Rock
igneous
Jasper and Agate Mix
Silicon dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz pebble with calcite
Silicon dioxide (SiO2) with Calcium carbonate (CaCO3)
sedimentary
Black Tourmaline
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
mineral
Likely tumbled jasper or iron-stained quartzite
Microcrystalline quartz (SiO₂), possibly quartzite with iron-oxide inclusions
metamorphic
Tumbled dark green stone, likely serpentine
Serpentinite; chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄), possibly with magnetite or chlorite
metamorphic
Tumbled green aventurine (probable)
Quartz aggregate, SiO₂, commonly containing fuchsite mica inclusions
mineral
Tumbled dark green stone, likely greenstone/serpentinite
Serpentinite (serpentine-group minerals, chiefly Mg₃Si₂O₅(OH)₄), possibly chlorite-rich greenstone
metamorphic
Tumbled dark green stone, likely serpentine or greenstone
Serpentinite (hydrated magnesium silicate minerals, chiefly antigorite/lizardite); possible chlorite-rich greenstone
metamorphic
Weathered quartz-rich stone (likely chert or quartzite)
Quartzite or microcrystalline quartz (SiO₂); exact identification is uncertain from the image
metamorphic
Ruby
Corundum (Al2O3 with Chromium impurities)
mineral
Polished greenstone, likely serpentine
Serpentinite (serpentine-group minerals, chiefly antigorite/lizardite; commonly with magnetite or chlorite)
metamorphic
Sandstone (Pebble)
Arenite (primarily SiO2)
sedimentary
Aventurine
Aventurine Quartz (SiO2 + Fuchsite mica)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Pyrite
Pyrite (Iron sulfide, FeS₂)
Mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Jasper and Agate
Microcrystalline Quartz (SiO2)
sedimentary
Pyrite
Pyrite (Iron Disulfide), FeS2
Mineral
Polished agate/geode fragment
Microcrystalline quartz (chalcedony), SiO₂, with possible calcite or quartz cavity lining
mineral
Polished greenstone (likely serpentinite)
Serpentinite, chiefly antigorite/lizardite Mg₃Si₂O₅(OH)₄, possibly with magnetite
metamorphic
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Black Tourmaline (Schorl)
Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartz (Gray/Smoky Variety)
Silicon Dioxide (SiO2)
mineral
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Mineral
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Massive White Quartz
Silicon Dioxide (SiO2)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral