This Is Not A Rock Or Mineral

Sandstone (Quartzose Sandstone)

Arenite

Olivine in Basalt (Peridotite Xenolith)

Forsterite-rich Olivine (Mg2SiO4) in Aphanitic Basalt

Sulfide Ore (likely Galena and Sphalerite in Quartz)

Lead-Zinc Ore (PbS and ZnS)

Basalt with Quartz/Calcite Vein

Basalt (Mafic Volcanic Rock with secondary mineralization)

Granite Gneiss

Gneiss (high-grade metamorphic rock)

Quartz (likely Herkimer Diamond style)

Silicon Dioxide (SiO2)

Peridot in Basalt

Olivine ((Mg, Fe)2SiO4) in Basalt

Basalt

Basalt (dominated by plagioclase feldspar and pyroxene)

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Magnetite

Magnetite (Fe3O4)

Granitic Pegmatite

Granite Pegmatite (coarse-grained intrusive igneous rock)

Sandstone (likely Quartzose)

Sandstone (Principally SiO2)

Granite Gneiss

Gneiss (High-grade regional metamorphic rock)

Banded Gneiss

Gneiss (Metamorphic Rock)

Granite

Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Copper-bearing Quartz (likely Chrysocolla or Malachite staining)

Cuprite, Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O) or Malachite staining on Quartz/Host Rock

Quartz / Common Opal

Silicon Dioxide (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Chalcedony

Cryptocrystalline Quartz (SiO2)

White Quartz (Tumbled)

Silicon Dioxide (SiO2)

Quartz (Milky/Yellowish variety)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Dyed Agate

Silicon Dioxide (SiO2)

Amygdaloidal Basalt with Epidote

Vesicular Basalt with secondary Epidote/Quartz mineral infill

Sandstone (Calcareous Sandstone)

Calcareous Sandstone (primarily SiO2 with CaCO3 cement)

Fossilized Bone Fragment

Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)

Quartz Druzy Geode

Silicon Dioxide (SiO2)

Diorite

Diorite (Intermediate intrusive igneous rock)

Lake Superior Agate

Cryptocrystalline Quartz (SiO2)

Carnelian and White Quartz Bracelet

Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz

Dyed Agate

Chalcedony (Silicon Dioxide, SiO2)

Limonite Concretion (Ironstone)

Limonite (FeO(OH)·nH2O) / Goethite

Druzy Quartz

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite (SiO2 with iron oxide impurities)

Turquoise in Matrix

Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O

Sandstone (likely Greywacke variant)

Arenite

Sandstone

Arenite (SiO2 based)

Turquoise

Hydrated phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O

Sandstone (Quartzose)

Arenite (composed mainly of SiO2)

Sandstone

Arenite (SiO2 based)