Anthropic Metallic Specimen

Native bismuth

Bismuth (Bi), commonly forming hopper crystals or aggregates

Quartz with Pyrite

Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)

Galena in Quartz Matrix

Lead Sulfide (PbS) in Silicon Dioxide (SiO2)

Magnetite / Hematite (Iron Ore Pebble)

Fe3O4 (Magnetite) / Fe2O3 (Hematite)

Blue Goldstone

Man-made glass with cobalt and metal flecks

Mica Schist with Pyrite

Mica Schist (FeS2 containing)

Pyrite in Quartz

Iron Sulfide (FeS2) embedded in Silicon Dioxide (SiO2)

Iron Meteorite (Campo del Cielo)

Iron Meteorite, Group IAB (FeNi Alloy: Kamacite and Taenite)

Pyrite-bearing metamorphic rock (likely schist or gneiss)

Pyrite (FeS₂) in a quartz–mica-rich host rock

Likely galena

Galena (lead sulfide, PbS)

Weathered sulfide-bearing ore specimen

Likely pyrite- and/or chalcopyrite-bearing quartz–iron-oxide rock; exact identification requires testing

Native gold nugget

Gold (Au), commonly with minor silver or copper

Native copper-bearing rock (probable copper ore)

Native copper (Cu), likely with copper sulfide/oxide minerals in a host rock

Aura Quartz (Coated Quartz)

Silicon Dioxide (SiO2) coated with vaporized metals

Not a rock, mineral, or geological specimen

Gold in Matrix

Native Gold (Au)

Pyrite (likely)

Iron disulfide, FeS₂; commonly called fool’s gold

Chalcopyrite

Copper Iron Sulfide (CuFeS2)

Hypersthene

Enstatite (Hypersthene variety), (Mg,Fe)SiO3

Gold Nugget

Native Gold (Au)

Weathered metallic sulfide-bearing rock, possibly chalcopyrite ore

Likely chalcopyrite (CuFeS₂) in a weathered host rock; identification is uncertain from the photograph

Fluorite on Matrix

Calcium Fluoride (CaF2)

Pyrite with Quartz

Iron Sulfide (FeS2) with Silicon Dioxide (SiO2)

Silver Nuggets (Natural or Cast)

Native Silver (Ag)

Gold in Quartz Matrix

Native Gold (Au) with Quartz (SiO2)

Native Copper in Basalt

Cu-element in Mafic Volcanic Rock (Basalt)

Magnetite Nodule

Magnetite (Fe3O4)

Pyrite

Iron Sulfide (FeS2)

Tiger Iron / Banded Iron Formation

Banded Iron Formation (SiO2 with Fe2O3 and FeOOH)

Galena-rich sulfide specimen

Galena (lead sulfide, PbS), possibly with sphalerite or other sulfides

Hematite

Iron (III) Oxide, Fe2O3

Gold Ore (in Quartz/Pyrite)

Native Gold (Au) with Quartz (SiO2) and Pyrite (FeS2)

Quartzite Pebble with Pyrite Coating

SiO2 (Quartz) with FeS2 (Pyrite) inclusions or surface coating

Basalt River Pebble (with possible Pyrite/Mineralization)

Basalt (Mafic volcanic rock)

Sunstone

Aventurine Feldspar (Plagioclase or Oligoclase)

Gold-bearing quartz fragment (probable native gold)

Native gold (Au) in quartz (SiO₂), identification uncertain from the photograph

Specular Hematite

Specularite (Iron Oxide, Fe2O3)

Galena with Pyrite

Lead Sulfide (PbS) associated with Iron Sulfide (FeS2)

Galena

Galena (lead sulfide, PbS)

Gold Ore in Quartz

Native Gold (Au) in Quartz (SiO2) matrix

Nuummite

Orthoamphibole (mixture of Anthophyllite and Gedrite)

Iridescent bismuth crystal

Bismuth (Bi), commonly laboratory-grown and oxide-coated