Metamorphic Rock (For Both Nephrite And Jadeite)

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Magnetite

Magnetite (Fe3O4)

Herkimer Diamond

Quartz (Silicon Dioxide, SiO2)

Possibly raw hematite or magnetite

Hematite (Fe₂O₃) or magnetite (Fe₃O₄)

Polished dark mineral fragments, likely hematite or magnetite

Hematite (Fe₂O₃) or magnetite (Fe₃O₄)

Black Tourmaline (Schorl)

NaFe3+3Al6(BO3)3Si6O18(OH)4

Black Tourmaline (Schorl)

Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)

Tumbled greenish stone, possibly serpentine or aventurine

Uncertain; likely serpentine-group mineral or quartz-rich green aventurine

Pyrite

Pyrite (Iron sulfide, FeS₂)

Jasper and Agate Mix

Silicon dioxide (SiO2) - Microcrystalline Quartz

Tumbled serpentine

Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and minor carbonate

Yellow faceted gemstone, likely citrine or yellow sapphire

Citrine: quartz, SiO₂; yellow sapphire: corundum, Al₂O₃

Sandstone (Quartzose type)

Arenite (primarily SiO2)

Black Tourmaline (Schorl)

Schorl (Sodium iron aluminum borosilicate hydroxide) NaFe3Al6(BO3)3Si6O18(OH)4

Tumbled green stone, likely serpentine

Serpentine-group minerals, commonly antigorite or lizardite; approximate formula Mg₃Si₂O₅(OH)₄

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Sandstone (Pebble)

Arenite (primarily SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Banded Quartzite Cobble

Quartzite (SiO2 with minor iron oxides)

Likely tumbled jasper or iron-stained quartzite

Microcrystalline quartz (SiO₂), possibly quartzite with iron-oxide inclusions

Likely tumbled jasper or agate

Microcrystalline quartz (SiO₂), possibly iron-rich jasper

Ruby

Corundum (Al2O3 with Chromium impurities)

Likely jade or green chalcedony cabochon

Possibly nephrite jade (actinolite–tremolite) or green chalcedony (microcrystalline quartz, SiO₂)

Tumbled greenstone (likely serpentine)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄

Quartz pebble with calcite

Silicon dioxide (SiO2) with Calcium carbonate (CaCO3)

Weathered quartz-rich stone (likely chert or quartzite)

Quartzite or microcrystalline quartz (SiO₂); exact identification is uncertain from the image

Black Tourmaline

Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)

Tumbled green-gray stone, likely aventurine quartzite

Quartz-rich quartzite, possibly fuchsite-bearing aventurine quartz (SiO₂)

Quartz Pebble

Silicon Dioxide (SiO2)

Tumbled greenstone, likely serpentine

Serpentinite; mainly antigorite/lizardite/chrysotile, Mg₃Si₂O₅(OH)₄

Light-colored tumbled stone, likely quartzite or marble

Quartzite (mostly SiO₂) or calcitic marble (CaCO₃); exact identification is uncertain from the image

Polished agate/geode fragment

Microcrystalline quartz (chalcedony), SiO₂, with possible calcite or quartz cavity lining

Greenstone

Metabasalts and metavolcanics

Green Aventurine

Quartzite with Fuchsite (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)

Polished serpentine

Serpentinite; chiefly serpentine-group minerals (lizardite, antigorite, chrysotile), Mg₃Si₂O₅(OH)₄

Quartz Pebble

Silicon Dioxide (SiO2)

Black Tourmaline (Schorl)

Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)

Calcite-rich limestone

Limestone, predominantly calcite (CaCO₃), possibly recrystallized

Quartz (Gray/Smoky Variety)

Silicon Dioxide (SiO2)