Anthropic Metallic Specimen

Native gold (gold nugget)

Native gold, Au; commonly alloyed with silver and copper (electrum when silver-rich)

Tumbled basalt

Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene with possible olivine

Pyrite (iron pyrite), possibly in a sulfide-bearing rock

Pyrite, FeS₂

Likely vesicular basalt (scoria)

Basaltic scoria; chiefly plagioclase, pyroxene, and olivine with volcanic glass

Banded iron formation fragment

Banded iron formation (BIF), chiefly hematite/magnetite and chert (SiO₂)

Possible metallic meteorite or iron-rich mineral

Uncertain; visually compatible with an iron meteorite, metal-rich chondrite, or magnetite-bearing rock

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Garnet Schist

Almandine-bearing Mica Schist

Quartz-rich rock fragment, possibly mica-bearing pegmatite

Likely quartz–feldspar–mica aggregate; exact identification requires testing

Ironstone / limonitic iron-rich rock

Goethite–hematite–limonite aggregate, commonly an ironstone concretion

Basalt Pebble

Basalt

Hematite (Concretion)

Iron(III) oxide (Fe2O3)

Basalt River Pebble

Basalt (Mafic Volcanic Rock)

Galena-bearing ore

Galena (lead sulfide, PbS), likely with quartz/carbonate gangue and weathered sulfides

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Schist with Schorl (Black Tourmaline)

NaFe3Al6(BO3)3Si6O18(OH)4 (Schorl)

Muscovite Schist with Quartz

Mica Schist (KAl2(AlSi3O10)(OH)2)

Polished blue-green metallic mineral specimen, likely bornite (“peacock ore”)

Bornite, Cu₅FeS₄; possibly chalcopyrite, CuFeS₂, with iridescent tarnish

Metallic sulfide-rich rock, possibly pyrite-bearing schist or marcasite specimen

Likely pyrite (FeS₂) in a foliated host rock; exact identification requires testing

Quartz with Sericite and Cinnabar

Silicon Dioxide (SiO2) with muscovite/sericite and mercury sulfide (HgS)

Man-made Jewelry Charm (Enameled Metal)

Not a natural mineral; composed of base metal alloy (likely zinc or brass) and epoxy resin/enamel.

Ironstone pebble

Ironstone (Ferruginous Sedimentary Rock)

Weathered concrete or cementitious slab (not natural rock)

Artificial calcium-silicate cement composite; likely Portland cement concrete

Basalt (Arrowhead form)

Extrusive mafic igneous rock

Basalt

Basalt (Mafic volcanic rock)

Possible iron-rich basalt or industrial slag

Basalt, likely Fe–Mg silicate rock; exact identification is uncertain from the blurred image

Native gold nugget (probable)

Native gold, Au; possibly gold-bearing quartz

Gold-bearing Quartz Ore

Auriferous Quartz (SiO2 + Au)

Basalt

Basalt (Mafic volcanic rock)

Basalt with Vesicular Texture

Basalt (SiO2 range 45-52%)

Iron-rich slag or ironstone; appearance is not diagnostic

Likely iron-oxide-rich material (hematite, Fe₂O₃, and/or magnetite, Fe₃O₄); possibly smelting slag

Pyrite (Fools Gold)

Iron Disulfide (FeS2)

Bismuth crystal

Bismuth (Bi), synthetic laboratory-grown crystal

Basalt (River Pebble)

Extrusive mafic igneous rock

Possible iron meteorite

Iron meteorite, likely an iron–nickel alloy (kamacite/taenite)

Pyrite

Iron Disulfide (FeS2)

Pyrite

Iron Disulfide (FeS2)

Pyrite

Iron Disulfide (FeS2)

Hematite bead bracelet

Hematite (iron(III) oxide, Fe₂O₃), likely polished specular hematite

Possible weathered basalt or slag fragment

Basalt, chiefly plagioclase and pyroxene; identification is uncertain from the image