Mineral (Metamorphic Pseudomorph)

Gneiss (specifically a Hornblende Gneiss or Micaceous Gneiss)

Gneiss (metamorphic rock composed primarily of quartz, feldspar, and mafic minerals)

Blue Quartzite

Quartzite (mostly SiO2 with mineral inclusions)

Schist

Mica Schist (Complex Silicates)

Marble

Metamorphic Limestone (Calcite, CaCO3)

Pyrite

Iron Sulfide (FeS2)

Magnetite (Lodestone variety)

Magnetite (Iron(II,III) oxide, Fe3O4)

Pyrite on Quartz

Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Epidote

Epidote (Ca2(Al, Fe)3(SiO4)3(OH))

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Vein in Hematitic Siltstone

Hydrothermal Quartz (SiO2) in Ferriferous Matrix

Fuchsite in Quartz

K(Al,Cr)2(AlSi3O10)(OH)2 in SiO2

Greenstone (metamorphosed basalt)

Greenschist / Meta-basalt

Weathered quartz-rich rock, likely quartzite or altered sandstone

Quartzite (mostly microcrystalline quartz, SiO₂); exact identification is uncertain from the photograph

Seven Chakra Bonded Stone

Bonded composite of Red Jasper, Carnelian, Tiger's Eye, Aventurine, Lapis Lazuli, Amethyst, and Clear Quartz

Greenschist

Greenschist facies rock

Pyrite

Iron Sulfide (FeS2)

Gneiss

Gneiss (a metamorphic rock)

Garnet

Garnet group [X3Y2(SiO4)3]

Corundum (Ruby variety)

Aluminium oxide (Al2O3)

River Quartzite Siltstone

Quartz-rich Meta-siltstone (SiO2 dominated)

Yellow Quartz

Silicon Dioxide (SiO2)

White Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Rhodonite

Rhodonite (MnSiO3)

White Jade (Nephrite)

Nephrite, Ca2(Mg,Fe)5Si8O22(OH)2

Marble

Recrystallized Calcite / Dolomite (CaCO3)

Purple Aventurine

Quartzite with Lepidolite (SiO2 + K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)

White Marble

Recrystallized Calcite (CaCO3)

Aventurine

Silicon Dioxide (SiO2) with inclusions

Marble

Metamorphosed Limestone (principally CaCO3)

Greenschist (containing Epidote and Quartz)

Greenschist (Epidote-Chlorite-Actinolite Schist)

Clear Quartz

Silicon Dioxide (SiO2)

Greenstone (Metabaltic/Greenschist)

Chlorite schist / Meta-basalt

Marble

Recrystallized Calcite (CaCO3)

Gneiss

Gneiss (Foliated Metamorphic Rock)

Pyrite Nodule

Iron Sulfide (FeS2)

Green Aventurine

Aventurine Quartz (SiO2 with inclusions of Fuchsite mica)

Tumbled pale quartz (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

Yellow Quartz (Citrine or Yellow Jasper)

Silicon Dioxide (SiO2) with iron impurities

Pyrite

Iron Sulfide (FeS2)

Agate (Polished Nodule)

Agate (Silicon Dioxide, SiO2)