Native gold is a naturally occurring metallic mineral, not an alloy made in a workshop. Its composition is gold, written Au. Most natural specimens also carry a little silver; when silver is abundant the variety is called electrum.
Gold is soft, dense, and malleable. It does not tarnish in air or water, which is why flakes and nuggets can remain bright in stream gravels. Crystals are uncommon and belong to the isometric system, usually as cubes, octahedra, or wiry groups. Much native gold is found as irregular masses, leaves, or grains in quartz veins and placer deposits.
This page is only for native gold. Hardness, formula, and crystal system below refer to this mineral alone.