Not A Geological Specimen

Granitic Pegmatite with Schorl

Granitic Pegmatite (NaAlSi3O8, KAlSi3O8, SiO2) with Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)

Dyed Magnesite (often sold as Red Turquoise or Howlite)

Magnesium Carbonate (MgCO3)

Diorite (Salt and Pepper Rock)

Phaneritic Plutonic Diorite; chemical composition roughly 52-63% silica (SiO2)

Pyrite

Iron Sulfide (FeS2)

Staurolite (Fairy Stone)

Staurolite (Fe2+2Al9Si4O23(OH))

Pyrite

Iron Sulfide (FeS2)

Blue Apatite

Fluorapatite / Chlorapatite [Ca5(PO4)3(F,Cl,OH)]

Biotite (Black Mica)

Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Sandstone (specifically an Iron-Concretion)

Arenite with Iron Oxide (Limonite/Goethite) cementation

Red Jasper (possibly Agatized Jasper)

Jasper (Silicon Dioxide, SiO2 with Fe2O3 inclusions)

Sandstone Pebble (Quartzite-rich)

Clastic Terrigenous Sedimentary Rock (SiO2 dominant)

Chert (and Jasper blend)

Chert (Microcrystalline Quartz, SiO2)

Calcite

Calcium Carbonate (CaCO3)

Sandstone (Ferruginous)

Ferruginous Sandstone (SiO2 with Fe2O3)

Quartzite

Quartzite (primarily SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hypersthene (or Enstatite/Ferrosilite)

Orthopyroxene series (Mg,Fe)SiO3 - specifically, historically hypersthene (intermediate member) now referred to as Enstatite (Mg-rich) or Ferrosilite (Fe-rich)

Azurite in Gossan

Azurite (Cu3(CO3)2(OH)2) in Limonite/Goethite matrix

Limonite/Goethite Nodule

Iron Oxyhydroxide (primarily FeO(OH)·nH2O)

Chert Breccia (Yellow Jasper)

Silicon Dioxide (SiO2) - Brecciated Chert

Chert (Jasper-like Silicate)

Microcrystalline quartz (SiO2)

Red Jasper

Jasper (Silicon Dioxide, SiO2)

Quartz (in a rock matrix)

Quartz (SiO2)

Pink Granite (Water-worn Cobble)

Phaneritic Felsic Intrusive Igneous Rock

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Chert (variations include Chalcedony and Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Granite Cobble

Granite (Phaneritic Quartz-Feldspar Felsic Rock)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Chalcopyrite

Chalcopyrite (CuFeS2)

Lepidolite

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lithium-bearing Mica)

Quartz with Iron Staining

Silicon Dioxide (SiO2)

Quartz with Pyrite

Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)

Ironstone Concretion (Limonite/Goethite)

Ferruginous Sandstone or Limonite (FeO(OH)·nH2O)

Lapis Lazuli (Tumbled Specimen)

Lapis Lazuli (Aggregate rock containing Lazurite: (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Granite Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Pyrite

Iron Sulfide (FeS2)

Basalt (with possible iron oxide staining)

Mafic Igneous Rock (primarily Plagioclase and Pyroxene)

Milky Quartz (river pebble)

Quartz (Silicon Dioxide, SiO2)

Grey Limestone Pebble

Limestone (Calcium Carbonate - CaCO3)