Home » Minerals » Gold

Gold


Mineral Properties and Geologic Occurrence


Article by: , PhD, RPG



Gold nuggets

Gold Nuggets from Colorado. These specimens range between three and eight millimeters across. They have the uniform color and rounded edges common of alluvial gold particles.

What is Gold?

Native gold is an element and a mineral. It is highly prized by people because of its attractive color, its rarity, resistance to tarnish, and its many special properties - some of which are unique to gold. No other element has more uses than gold. All of these factors help support a price of gold that is higher than all but a few other metals.

ADVERTISEMENT


Trace amounts of gold are found almost everywhere, but large deposits are found in only a few locations. Although there are about twenty different gold minerals, all of them are quite rare. Therefore, most gold found in nature is in the form of the native metal.

Gold occurs in hydrothermal veins deposited by ascending solutions, as disseminated particles through some sulfide deposits, and in placer deposits.

The most obvious physical property of gold is its color. It is one of just a few minerals whose names are used frequently in common language as the name of a color. The color is not altered by tarnish or the development of an oxidized surface. However, the color of gold varies with its composition. The color of gold is not constant.

vein gold

Vein gold: White "vein quartz" with gold from Colorado. This specimen is approximately one inch (2.5 centimeters) across.

ADVERTISEMENT


Physical Properties of Gold

Chemical Classification Native element
Color Golden, yellow. Whitens when naturally alloyed with silver.
Streak Golden, yellow.
Luster Metallic, without tarnish.
Diaphaneity Opaque
Cleavage None
Mohs Hardness 2.5 to 3
Specific Gravity 19.3 when pure. Specific gravity decreases as gold naturally alloys with silver, copper or other metals.
Diagnostic Properties Color, hardness, streak, specific gravity, ductility, malleability.
Chemical Composition Gold, Au
Crystal System Isometric
Uses Many uses in jewelry, coinage, and bullion. Gold is an electrical conductor used in computers, circuits, appliances, cell phones, etc. Dental work, gilding, and many other uses.

gold in quartz vein

Vein gold: Vein quartz with gold attached to basalt from California. This specimen is approximately 1 inch (2.4 centimeters) across.

Uses of Gold

2019 Gold Production
Country
Metric Tons
China420
Australia330
Russia310
United States200
Canada180
Indonesia160
Ghana130
Peru130
Mexico110
Kazakhstan100
The values above are estimated gold production in metric tons. Data from USGS Mineral Commodity Summaries.

Most of the gold that is newly consumed or recycled each year is used in the production of jewelry. About 10% is used in coinage or in the financial stores of governments. The remaining 12% is consumed in a wide range of other uses which include electronics, medicine, dentistry, computers, awards, pigments, gilding, and optics. More information on the uses of gold.

World Gold Production Map

World Gold Production Map: Which countries produce the most gold? The top ten gold-producing countries are shown in green on the map above. See the chart on this page for gold production statistics for each country.

ADVERTISEMENT


Mineral collection

The best way to learn about minerals is to study with a collection of small specimens that you can handle, examine, and observe their properties. Inexpensive mineral collections are available in the Geology.com Store. Image copyright iStockphoto / Anna Usova.

More Minerals
  Rhodochrosite
  Grape Agate
  Copper
  Topaz
  What Is Benitoite?
  Diopside
  Fool*s Gold
  Quartz

geology store

Find Other Topics on Geology.com:


Rocks
Rocks: Galleries of igneous, sedimentary and metamorphic rock photos with descriptions.
Minerals
Minerals: Information about ore minerals, gem materials and rock-forming minerals.
Volcanoes
Volcanoes: Articles about volcanoes, volcanic hazards and eruptions past and present.
Gemstones
Gemstones: Colorful images and articles about diamonds and colored stones.
General Geology
General Geology: Articles about geysers, maars, deltas, rifts, salt domes, water, and much more!
Geology Store
Geology Store: Hammers, field bags, hand lenses, maps, books, hardness picks, gold pans.
Earth Science Records
Earth Science Records: Highest mountain, deepest lake, biggest tsunami and more.
Diamond
Diamonds: Learn about the properties of diamond, its many uses, and diamond discoveries.