Where does gold come from?
Did you know that gold is really: extraterrestrial?
Made by the stars
Gold is the beautiful shiny precious metal that has been sought after by mankind, just as long as we can remember. The shine and lustre have always attracted us and we have attributed much meaning to the metal itself. But let’s take a look where gold actually comes from! We already revealed that it is made in the stars, but it goes even further: gold is made by the stars. It was created, by all sorts of chemical reactions in space and it ended up in our planet’s crust where it can be found still today.
Gold comes from supernovae
Stars are made up of hydrogen. This is an element that is both the most simple and lightest. However, the enormous -quoting here- gravitational pressure of so much material compresses and triggers nuclear fusion in the star’s core. And this why stars shine! That energy that gets released from the hydrogen is actually what makes a star shine.
After millions of years, things change. The hydrogen gets transformed by fusion in three elements: carbon, oxygen and helium. Bear with me for this science lesson: whilst transforming it burns subsequent elements increasingly faster to reach iron and nickel. Now energy can no longer be just released and pressure from the core starts petering out. Outer layers collapse and to tell a longer story really short: the star explodes. Exploding stars are also known as supernovae.
So the supernova, is not just an extreme force, but also a very spectecular one. During the explosion this is what happens: it forms subatomic protons and electron together in the core forming neutrons. Neutrons have no repelling electric charge so...they are captured by the iron group elements. Multiple neutron captures enables the formation of heavier elements from silver to gold, past lead and on to uranium. All this happens in just a few seconds!
Gold gets delivered by the stars to our planet
Supernova create also the start of new planets and stars, but we think that the gold found on planet Earth was most probably delivered to us, by a nearby collapsing star. It got worked into our crust after another very long time.
Gold is not just rare, it is also rather expensive to mine. In terms of money (and surely in times of human efforts and lives lost, families ruined and so forth)
This is what I found most astonishing:
Did you know that the amount of gold mined so far actually fits into three...3!...Olympic size swimming pools? Ok, so gold is 20 times denser than water, still it remains a weird thought that this metal, so important for our economies, is just three swimming pools full. It's a lot, yet so much less than I personally thought.
Where is gold used for?
Gold is stored as a hedge against inflation or other economic disruptions. 50 % of gold is used for jewelry, 40% as investment and 10 % in industry. What industry you ask? Well, it is used within a computer but also within a cell phone. Don’t break it open just yet. The value is around 50ct per phone, but all in all there is an estimated 500 million dollars of gold in all the cell phones in the world combined. Perhaps even more as the article I read this from dates back to 2014.
Can we produce gold ourselves?
Well, theoretically yes. The dream of alchemists is coming true...but not just quite. See, it takes almost as long as the age of the Universe to produce one gram. As a machine would only be able to create gold, atom by atom.
What happens if we finish to mine all the gold in the world?
Well, the ocean holds gold too. And a lot of it! Luckily for the environment of that sea, the gold is dissolved and way too costly to recover from the sea.
Where can we find more gold.
Perhaps we will create one day missions to start mining it from other planets? Or...another supernova will take place close enough to once again bring us our beloved yellow precious metal.
Source: Ted Ed
ps. we highly recommend Ted Ed for many informative video's