Where did all the gold on Earth originally come from?
All of the gold that's deposited in our planet was formed during the explosions of stars and collisions of asteroids, and eventually found its way to earth over time. Today, gold is one of the most valuable precious metals and rarest natural minerals.
Gold — atomic number 79, element symbol Au, the most widely beloved of the precious metals — might have its origin in extremely rare and violent explosions in the far reaches of outer space.
Pressure changes cause precious metal to deposit each time the crust moves. Scientists have long known that veins of gold are formed by mineral deposition from hot fluids flowing through cracks deep in Earth's crust.
Though new gold mines are still being found, discoveries of large deposits are becoming increasingly rare, experts say. As a result, most gold production currently comes from older mines that have been in use for decades.
During the biblical period, just as today, gold served as a store of value, a symbol of wealth and prominence, and a jewelry metal. It was obtained in trade mainly from sources in Egypt, the Arabian Peninsula, India, and the Sinai Peninsula.
Did you know that gold is extraterrestrial? Instead of arising from our planet's rocky crust, it was actually cooked up in space and is present on Earth because of cataclysmic stellar explosions called supernovae. CERN Scientist David Lunney outlines the incredible journey of gold from space to Earth.
While nuclear fusion within the Sun makes many elements, the Sun cannot synthesize gold. The considerable energy required to make gold only occurs when stars explode in a supernova or when neutron stars collide. Under these extreme conditions, heavy elements form via the rapid neutron-capture process or r-process.
As such, no series of chemical reactions can ever create gold. Chemical reactions change the number and shape of the electrons in an atom but leave the nucleus of the atom unchanged. The ancient alchemist dream of creating gold by simply reacting chemicals is therefore impossible.
Gold Discovery in Egypt
They mined gold in Nubia around 2450 BC. An Egyptian alchemist named Zosimos was the first to find pure gold (24 centuries before Columbus reached the Americas). The discovery of gold is attributed to the ancient Egyptians, who made jewelry out of gold.
Gold is thought to have been produced in supernova nucleosynthesis, and from the collision of neutron stars, and to have been present in the dust from which the Solar System formed.
Where is gold naturally found on Earth?
Gold is primarily found as the pure, native metal. Sylvanite and calaverite are gold-bearing minerals. Gold is usually found embedded in quartz veins, or placer stream gravel. It is mined in South Africa, the USA (Nevada, Alaska), Russia, Australia and Canada.
The moon isn't so barren after all. A 2009 NASA mission—in which a rocket slammed into the moon and a second spacecraft studied the blast—revealed that the lunar surface contains an array of compounds, including gold, silver, and mercury, according to PBS.
Gold is an extremely rare element on Earth. Because it doesn't react with very many other elements, it is often found in its native form in the Earth's crust or mixed with other metals like silver. It can be found in veins underground or in small fragments in sandy riverbeds.
First found at surface level near rivers in Asia Minor such as the Pactolus in Lydia, gold was also mined underground from 2000 BCE by the Egyptians and later by the Romans in Africa, Portugal and Spain. There is also evidence that the Romans smelted gold particles from ores such as iron pyrites.