Mineral (Iron Ore)

Tiger Iron

Tiger Iron (composite of Tiger's Eye, Red Jasper, and Hematite)

Metal Alloy (Jewelry)

Not a naturally occurring rock or mineral; likely a metal alloy for jewelry. Possible compositions include sterling silver (92.5% silver, 7.5% copper), or other silver/gold alloys.

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Green Fluorite

Calcium Fluoride (CaF2)

Rhodonite

Rhodonite (MnSiO3)

Orange Calcite (likely polished specimen)

Calcite

Ferruginous Quartz

Silicon Dioxide with Hematite/Limonite inclusions (SiO2 + Fe2O3)

K2 Azurite Granite / K2 Stone

Granite (igneous rock) with Azurite inclusions (mineral)

Sandstone (Ferruginous)

Arenite with Iron Oxides

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

Quartz Pebble (Citrine-colored or Stained Quartz)

Silicon Dioxide (SiO2)

Orange Quartz

Crystalline Silicon Dioxide (SiO2) with iron oxide inclusions

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Lapis Lazuli (Raw Ore)

Na8[Al6Si6O24]n(S,Cl,SO4,OH)2 (Lazurite component)

Ferruginous Quartz (Stained Quartz)

Silicon Dioxide (SiO2) with secondary Iron Oxide inclusions (Limonite/Hematite)

Gold Ore / Native Gold

Native Gold (Au)

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with iron oxide inclusions/staining (Limonite/Hematite)

Lepidolite in Quartz (or Lepidolite Ore)

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2) in Quartz (SiO2)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Iron-Nickel Meteorite fragment

Siderite (meteoritic iron), composed primarily of Kamacite (α-(Fe,Ni)) and Taenite (γ-(Fe,Ni))

Bronzite

MgSiO3 (Enstatite with 10-30% FeSiO3 in solid solution)

Vesicular Basalt (Amygdaloidal)

Amygdaloidal Basalt (Mafic volcanic rock)

Basalt with Iron Oxides

Mafic Igneous Rock (Mafite)

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.

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Manganese Ore (Psilomelane/Pyrolusite)

Psilomelane ((Ba,H2O)2Mn5O10) and Pyrolusite (MnO2)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide cement)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Sandstone concretion (Ironstone-stained)

Arenite with Limonite/Hematite staining (Silica-based with Iron Oxides)

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Iron-stained Quartz

Silicon Dioxide with Iron Oxide (SiO2 with Limonite/Hematite impurities)

Rhodonite

Rhodonite (MnSiO3)

Galena

Lead(II) sulfide (PbS)

Bog Iron / Limonite Concretion

Goethite/Limonite mixture (FeO(OH)·nH2O)

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide with Iron Oxide (SiO2 with traces of Fe2O3/FeO(OH))

Yellow Quartz River Pebble

Silicon Dioxide (SiO2)

Slate with Quartz

Low-grade Metamorphic Slate with SiO2 inclusions

Ferruginous Quartz (Carnelian-tinted Quartz)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Fluorite (often referred to casually as 'Fluorspar' in industrial contexts)

Fluorite (CaF2)

Cinnabar

Cinnabar (HgS)