Industrial Byproduct (Often Mistaken For Obsidian Or Mineral)

Sandstone

Arenite

Grey Chalcedony

Silicon Dioxide (SiO2)

Dyed Magnesite (Howlite imitation)

Magnesium carbonate (MgCO3) with dye

Sandstone with Foliose Lichen

Arenite (Rock matrix) with Xanthoparmelia or Flavoparmelia (Lichen genus)

Diamond (Cluster Ring)

Carbon (C)

Almandine Garnet (weathered)

Almandine (Fe3Al2(SiO4)3)

Rough Corundum (likely Sapphire/Zircon-bearing)

Aluminium Oxide (Al2O3)

Milky Quartz (Water-Worn Pebble)

Silicon Dioxide (SiO2)

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Basalt with Sulfide/Pyrite inclusion

Aphanitic Mafic Igneous Rock (likely Basalt) with Pyrite (FeS2)

Rainbow Fluorite

Calcium Fluoride (CaF2)

Blue Sapphire

Corundum (Al2O3)

Gold and Diamond

Native Gold (Au) and Diamond (C)

Garnet Schist

Almandine Garnet Schist

Magnetite / Ironstone

Iron(II,III) oxide (Fe3O4)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Blue Lepidolite

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)

Blue Calcite

Calcium Carbonate (CaCO3)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Quartz with Mica inclusion

Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions

Yellow Calcite (Banded Calcite)

Calcium Carbonate (CaCO3)

Porphyritic Basalt

Basalt (Mafic Extrusive Igneous Rock)

Magnetite / Iron Ore

Magnetite (Fe3O4)

Orange Calcite (Banded Honey Calcite)

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Bauxite

Hydrated Aluminum Oxides (primarily Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Diaspore α-AlO(OH))

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

Sapphire

Corundum (Al2O3)

Golden Healer Quartz

Ferruginous Quartz (SiO2 with Fe2O3 inclusions)

Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)

Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)

Quartzite

Quartzite (primarily SiO2)

Sandstone (lithic wacke)

Arenite / Lithic Wacke (mostly SiO2 with rock fragments)

Orange Calcite

Calcium Carbonate (CaCO3)

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Quartz with inclusions

Silicon Dioxide (SiO2)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix

Apache Tear

Obsidian (Hydrated Silica Rich Volcanic Glass)

Garnet (Almandine)

Almandine (Fe3Al2(SiO4)3)

Agate

Chalcedony (Cryptocrystalline variety of Quartz, SiO2)

Quartz with Mica (Gneissic or Pegmatitic origin)

Silicon Dioxide (SiO2) with Phyllosilicates (KAl2(AlSi3O10)(F,OH)2)

Dolomite on Prehnite (Saddle-shaped Dolomite)

Dolomite [CaMg(CO3)2] on Prehnite [Ca2Al(AlSi3O10)(OH)2]

Orange Calcite

Calcium Carbonate (CaCO3)