Native metal

A naturally occurring metal found in uncombined or nearly pure elemental form rather than chemically bound in a compound. Native metals persist where geological conditions prevent their oxidation or other chemical reactions.

Chemical element: A pure substance made of atoms with the same number of protons. Native metals consist of one chemical element, not a chemically bonded mineral compound.
Electrochemical series: An ordering of chemical species by their standard electrode potentials. It helps explain why noble metals are less readily oxidized than reactive metals.
Native silver: Silver occurring naturally in elemental form, sometimes alloyed with other metals. It demonstrates that a relatively unreactive metal can occur native but also form compounds.
Copper metallurgy: The extraction, refining, and working of copper and copper alloys. Native copper could be shaped before smelting techniques made ore-based production practical.
Mineral: A naturally occurring solid with a defined chemical composition and an ordered atomic structure. Native metals are classified as minerals when they meet mineralogical criteria.
Weathering: The breakdown and alteration of rock and minerals at or near Earth’s surface. Weathering can dissolve surrounding material and concentrate resistant native-metal grains.
Native platinum: Platinum occurring naturally as metal, commonly with iron and other platinum-group elements. Its alloys show that native metals need not be chemically pure.
Gold mining: The extraction of gold from deposits, including veins and sedimentary placers. Native gold grains and nuggets are direct targets of mining and panning.
Oxidation: A chemical process in which an atom or ion loses electrons. Resistance to oxidation helps elemental metals survive in Earth’s crust.
Hydrothermal circulation: The movement of heated water through fractures and pores in rock. Hydrothermal fluids transport metals and can precipitate native forms when conditions change.

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