Gold was so important to the Egyptians that pharaohs were sometimes buried in solid gold coffins with amulets, jewellery and other treasures. The precious metal played a huge role in the Ancient Egyptian society; fast forward to today, and we’ve used gold as a currency, jewellery and even as a substitute for teeth. Its rarity and unique properties means that it holds a special place in our culture, and will likely do so for centuries to come. But how is gold made? Where does it come from? And the question we’ve asked ourselves for centuries… can you “create” gold?
Believe it or not, gold comes from space. Specifically, it comes from inside a star, such as the Sun (the Egyptians were not so far off!). Stars are made of helium and hydrogen, and inside that core is energy. When a star collapses and causes an explosion called a supernova, the intense pressure causes a collision of atoms which creates a much heavier element: gold.
Our planet was created from a collision of stars and asteroids, back 4.5 billion years ago. Thanks to the collision of dead stars, we now have gold on our Earth.
As we mentioned above, gold was created from explosions which then collided and created the Earth’s core. But where do you find gold on Earth? You’ll mostly find gold in rock ore and at the bottom of the ocean. Earth events like earthquakes accumulate more gold, making it easier for us to find it. The largest known deposits of gold are based in India and South Africa.
According to the World Gold Council, 190,000 metric tons of gold have been mined to date. Although that may sound like a lot, it’s actually only the size of 4 Olympic swimming pools. We haven’t mined that much gold, but there is actually still a lot left on Earth: almost 20 million tonnes are sitting in the ocean in the form of tiny particles. However, as we’ll see below, it’s too expensive to gather that type of gold.
Usually, gold is found in its purest state: in rock ore. However, it can also be extracted from other metals and found in rivers. There are two different types of gold deposits and miners use different techniques depending on the type of deposit.
The first type of deposit is called a vein deposit: this is where gold is mixed with another mineral in a specific vein in a rock. Miners need to drill and blast the rock in order to access it. The gold ore is then gathered and taken to a refinery.
The second type of deposit is called placer deposits: these are essentially small grains of gold which can be found in a river. This gold is usually mixed with gravel and sand and must be sifted through to be accessed. When gold is gathered through placer deposits, it needs to go through various processes before becoming a gold bar: grinding, separating gold from ore and smelting.
Today, most gold mining operations are on the surface and are operated by gold mining companies such as Goldcorp and Barrick Gold.
Unlike many other metals and materials, gold can be recycled. This means that even if there is no gold left to mine, we won’t run out of it. Currently, gold is used in many electronic products, dentistry and satellites, which can be recycled and reused.
Every year, 2,500 to 3,000 tonnes of gold are added to the above-ground stock of gold. Although production increases every year, it will start levelling off. Mining production was 1% lower in 2019 than in 2018, which makes some experts believe that we’ve already reached “peak gold”, meaning we may have maxed out the total amount we can mine in a year. Estimates say there is 20% of our total gold stock left to be mined (not the seawater gold), which translates into 50,000 tonnes of below the ground reserves. If experts are correct, the gold production may decrease in the coming few years, although it’s unlikely it’ll be dramatic.
There are a few other places we could get gold such as Antarctica, the ocean floor and the moon, but it’s often more expensive than the value of selling gold, and therefore not worth mining.
Good question! The short answer is no. In fact, people have been trying to make man-made gold for centuries! These people were called alchemists, and they spent hours with various liquids figuring out how to make gold from lead.
Nowadays, there is such a thing as synthetic gold. This is gold that is created through a bacterial reaction, rather than nuclear reactors or mercury. Synthetic gold has the same properties as natural gold: it is ductile, it conduces electricity, it is malleable and it has the same bright yellow colour. Having said that, it is not as valuable as gold and is not used as an investment or a substitute for gold bullion.
If we wanted to make real, pure gold, we would have to imitate the reaction that happens in a star here on Earth. We can do that using supercolliders, which physicists have been able to do – however, it does require making one atom of gold at a time using a supercollider. If 200 grams of gold contains billions of atoms of gold and you can only make one atom per hour, then it would be billions of years before we could create 200 grams of gold!
Gold comes from the debris of dead stars. It is usually found in rock ores and at the bottom of the ocean.
It took over 4.5 billion years since the formation of our planet when meteorites bombarded Earth.
From gold mine to gold ingot, it takes 10 – 20 years for a mine to produce anything that can be refined.
China is the largest miner of gold, but the US owns the most gold with 8,133 tonnes of gold worth more than $373 billion. Having said that, it’s difficult to say exact numbers since the Chinese and Russians are not fully transparent about their deposits.