Mineral Like Biological Tissue

Green Aventurine (Quartz)

SiO2 (Silicon Dioxide with Fuchsite inclusions)

Quartz

Quartz (SiO2 - Silicon Dioxide)

Marble

Recrystallized Calcite Rock (CaCO3)

Granite

Phaneritic Plutonic Igneous Rock (composed of Quartz, Feldspar, and Mica)

Basalt with Epidote (Flowerstone-like texture)

Amygdaloidal Basalt (silicate mineral inclusions)

Blue Agate (likely Dyed)

Silicon Dioxide (SiO2) - Chalcedony variety

Sandstone (Stream Pebble)

Arenite (primarily SiO2)

Ruby in Zoisite (Anyolite)

Corundum var. Ruby in Zoisite (Al2O3 + (Ca2Al3(SiO4)3(OH)))

Sandstone

Arenite (primarily SiO2)

Sandstone (Calcareous Sandstone)

Calcareous Sandstone (primarily SiO2 with CaCO3 cement)

Sandstone

Arenite (composed primarily of SiO2)

Granite

Granite (composed primarily of Quartz SiO2, Alkali Feldspar KAlSi3O8, and Plagioclase)

Vesicular Basalt with Oxidation

Scoriaceous Olivine Basalt (Mafic volcanic rock)

Milky Quartz (Stained with Iron)

Silicon Dioxide (SiO2)

Quartz (Iron-Stained Quartz Pebble)

Silicon Dioxide (SiO2)

Almandine Garnet

Iron aluminum silicate (Fe3Al2(SiO4)3)

Biotite Schist

Biotite Schist

Blue Calcite (commonly sold as Caribbean Calcite)

Calcium Carbonate (CaCO3)

Granite

Granite (Phaneritic Quartz-Feldspar intrusive rock)

Moss Agate

Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite

Quartz (Druzy Quartz)

Silicon Dioxide (SiO2)

Sandstone

Arenite (primarily SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Granitic Gneiss

Gneiss (containing Potassium Feldspar and Quartz)

Mica Schist

Mica Schist (predominantly Muscovite or Biotite sheet silicates)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Granite

Granite (Felsic Plutonic Rock)

Granite with Mafic Inclusions

Granite (Phaneritic igneous rock composed of Quartz, Feldspar, and Mica)

Schorl (Black Tourmaline) in Quartz or Feldspar Matrix

NaFe3Al6(BO3)3Si6O18(OH)4 (Schorl) in Granitic Pegmatite

Desert Rose

Gypsum (variety Selenite) or Barite, CaSO4·2H2O

Quartz Geode

Silicon Dioxide (SiO2)

Quartz Pebble (Citrine-colored or Stained Quartz)

Silicon Dioxide (SiO2)

Mica Schist

Mica Schist

Massive Quartz (Milky or Gray)

Silicon Dioxide (SiO2)

Emerald (Faceted Gemstone)

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sunkissed Quartz or Hematoid Quartz

Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions

Sandstone (Quartzite-rich Cobble)

Clastic sedimentary rock (primarily SiO2)

Pyrite (Iron Pyrite)

Iron Sulfide (FeS2)

Rhodonite

Rhodonite (MnSiO3)

Sandstone with Iron Oxide

Arenite (SiO2 with Fe2O3 staining)

Sandstone (Quartzite-rich River Cobble)

Clastic sedimentary rock (primarily SiO2)