Mineral Specimen

Quartz Pebble (Milky Quartz)

Silicon Dioxide (SiO2)

Turquoise (Blue Howlite imitation)

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

Quartz Pebble (Sea Glass-like texture)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

White Quartz (Milky Quartz)

Quartz (Silicon Dioxide - SiO2)

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)

Satin Spar (often marketed as Selenite)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Yellow Chalcedony (Agate Pebble)

Silicon Dioxide (SiO2)

Purple Chalcedony (likely dyed Agate)

Silicon Dioxide (SiO2)

Lepidolite on Pegmatite

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

Rose Quartz

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

Shale with Plant Fossils / Carbonaceous Shale

Laminated Mudrock (Siliciclastic)

Yellow Quartzite (River Cobble)

Quartzite (SiO2)

Granite

Phaneritic Felsic Igneous Rock

Gneiss

Metamorphic rock of high-grade regional metamorphism

Quartz Pebble

Silicon Dioxide (SiO2)

Yellow Chalcedony (Agate/Carnelian variant)

Silicon Dioxide (SiO₂)

Green Jasper

Silicon Dioxide (SiO2) with impurities

Yellow Quartz / Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble (with Manganese dendrites/staining)

Silicon Dioxide (SiO2) with Manganese Oxide impurities

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) in Rhyolitic Matrix

Limonite and Goethite encrusted Chert/Ironstone

Hydrated Iron Oxide (FeO(OH)·nH2O) with cryptocrystalline Silica (SiO2)

Milky Quartz (Water-worn Pebble)

Quartz (Silicon Dioxide, SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Malachite

Copper Carbonate Hydroxide [Cu2CO3(OH)2]

Schorl (Black Tourmaline) in Quartz Matrix

Schorl: NaFe3Al6(BO3)3Si6O18(OH)4 (Complex Borosilicate)

Grooved Maun Ball (Maul/Hammerstone-like Concretion)

Calcareous/Ferruginous Concretion in Sandstone Matrix

Chert Breccia (Yellow Jasper)

Silicon Dioxide (SiO2) - Brecciated Chert

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Charoite

Charoite (K(Ca,Na)2Si4O10(OH,F)·H2O)

Fluorite

Fluorite (CaF₂)

Sodalite

Sodalite (Na8Al6Si6O24Cl2)

Lepidolite

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

Orange Calcite

Calcium Carbonate (CaCO3)

Orange Quartzite / Aventurine

Silicon Dioxide (SiO2)

Basalt with Quartz Vein

Basalt (SiO2 vein inclusion)

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

Dyed Magnesite (often sold as Red Turquoise or Howlite)

Magnesium Carbonate (MgCO3)

Magnetite (potentially as a Lodestone or within Ironstone)

Magnetite (Fe3O4)

Pearl (Biogenic Mineraloid)

Calcium carbonate (Aragonite) and Conchiolin, CaCO3

Note: Item is not a geological specimen

Guitar Components (Steel, Nickel, Plastic, Wood)

Slag (Industrial Byproduct)

Artificial silicate/iron byproduct