Mineral

Picture Jasper

Silicon Dioxide (SiO2) with mineral inclusions

Sandstone (likely Siltstone variety)

Arenite / Siltstone (primary mineral SiO2)

Chert (Serpentinized)

Silicon Dioxide (SiO2) with mineral staining

Strawberry Quartz

Quartz (SiO2) with inclusions of Goethite or Hematite

Milky Quartz with inclusions

Silicon Dioxide (SiO2)

Pyrite

Iron Disulfide (FeS2)

Limestone with Quartz/Calcite Veins

Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)

Greenstone

Greenschist (containing chlorite, epidote, and actinolite)

Sandstone (Ferruginous)

Arenite (SiO2 with Fe2O3 inclusions)

Psilomelane (Black Hematite/Manganese Ore)

Barium Manganese Oxide (Formula: BaMn9O18(OH)4)

Geode with Iron-Stained Quartz/Calcite

Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix

Red Sandstone

Quartz Arenite (with Iron Oxide)

Basalt (Greenstone)

Basalt with chlorite/epidote (often referred to as Greenstone)

Red Sandstone

Arenite (primarily Quartz SiO2 with Hematite Fe2O3 cement)

Red Sandstone

Arenite (primarily composed of SiO2 with Fe2O3 cement)

Granite

Granite (a phaneritic intrusive igneous rock consisting mainly of quartz, alkali feldspar, and plagioclase)

Quartz with Muscovite Mica

Silicon Dioxide (SiO2) with Potassium aluminum silicate hydroxide fluoride [KAl2(AlSi3O10)(F,OH)2]

Granite (Phaneritic Igneous Rock)

Granite

Gabbro

Basaltic Plutonic Rock (Gabbro)

Auriferous Quartz (Gold-bearing Quartz)

Silicon Dioxide (SiO2) with trace Gold (Au) and Iron Oxides

Limonite

Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)

Blue Quartzite (Aventurine)

Silicon Dioxide (SiO2) with mineral inclusions

Prehnite

Prehnite - Ca2Al(AlSi3O10)(OH)2

Amygdaloidal Basalt with Epidote

Vesicular Basalt with secondary Epidote/Quartz mineral infill

Silver (Native Element)

Ag (Argentum)

Bauxite

Alumina ore (Mixture of Gibbsite, Boehmite, and Diaspore)

Quartz (Druzy)

Silicon Dioxide (SiO2)

Magnetite (in matrix)

Magnetite (Fe3O4)

Amygdaloidal Basalt

Amygdaloidal Basalt

Sandstone (Calcareous or Ferruginous)

Clastic sedimentary rock (SiO2 with CaCO3 or Fe2O3 cement)

Vesicular Basalt with Amygdaloidal Infill

Basalt (Mafic Extrusive Igneous Rock)

Granite

Granite (Felsic Plutonic Rock)

Brecciated Chert

Sedimentary Chert (SiO2) with Calc-Silicate mineralization

Jasper (var. Ocean or Polychrome Jasper)

Silicon Dioxide (SiO2) with iron and mineral inclusions

Olivine (Peridotite)

Magnesium iron silicate (Mg, Fe)2SiO4

Sandstone

Clastic sedimentary rock (primarily SiO2)

Gneiss

Gneissic Metamorphic Rock

Magnetite / Ironstone Pebble

Magnetite (Fe3O4)

Chrysocolla

Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)

Rose Quartz

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

Banded Gneiss

Gneiss (High-grade Metamorphic Rock)

Azurite-Malachite (often a mixed specimen)

Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2(CO3)(OH)2. The specimen appears to be a natural mixture or intergrowth of these two minerals.