字幕列表 影片播放 列印英文字幕 A single ounce of gold is roughly the size of a sugar cube and currently sells for nearly $1,300. Gold has been part of the world's many monetary systems for thousands of years and banks still hold gold reserves as a store of value, as an asset, and as financial insurance should they hit economic turmoil. It's a rare metal that costs a great deal to mine, which is one of the reasons it holds value. How rare is it? That's what we intend to find out, in this episode of The Infographics Show: How Much Gold Is There In The World? Ok, so before we work out how much gold there is in the world, let's first talk about what gold is and why it is so valuable. Silver has far more industrial uses. Copper is much more plentiful and has superior electrical conductivity, and Platinum and palladium are both more rare and the best-known metals to reduce harmful auto emissions. But what gold has going for it, is it's superior chemical properties. Gold cannot be destroyed by water, as it doesn't rust; by time, coins remain recognizable after a thousand years; by fire it takes 1945.4° F to melt it; Gold is also uniquely malleable, as it spreads without cracking; it's ductile, as it stretches without breaking; and most importantly gold is very rare. It's estimated that all the gold ever found would only fill two Olympic-sized swimming pools. The purchasing power of gold has also endured throughout the centuries. 2,000 years ago, during the time of Christ, an ounce of gold would buy a Roman citizen his toga, complete with a leather belt, and a pair of sandals. Today, one ounce will still buy a good suit, a leather belt, and a pair of shoes. In 400 BC, during the reign of King Nebuchadnezzar, an ounce of gold would buy you 350 loaves of bread. Today, an ounce still buys you about 350 to 400 loaves, assuming the average cost of a loaf is around $3.50. And in 1978, gold averaged $193 an ounce, so it took roughly 290 ounces of gold to buy a median priced house in the US. In 2014, gold had risen to around $1,266 an ounce, so it took only 225 ounces of gold to buy the median priced house in the US. Gold not only holds its value, it boosts your purchasing power. So how much of this heavy glowing metal is there out in the world, and who has their hands on it? The United States holds the largest gold reserve at more than 8,000 metric tons, which is worth more than $375 billion. These reserves were a significant portion of the country's $850 billion monetary base in 2008, but since then, it has become a smaller portion of the monetary base, which was $4 trillion by 2017. By comparison, China holds less than 3 percent of its reserve holdings in gold. While the U.S. holds the largest gold reserves, other countries are adding to their reserves at a faster rate or have access to domestic gold sources. The countries with the largest gold reserves, as of June 2017 are: United States 8,133.5 metric tons, Germany 3,374.1 metric tons, Italy 2,451.8 metric tons, France 2,435.9 metric tons, China 1,842.6 metric tons, Russia 1,715.8 metric tons, and Switzerland 1,040.0 metric tons. The International Monetary Fund or IMF also holds 2,814 metric tons of gold, while the European Central Bank, or ECB holds about 504.8 metric tons in its reserves. These are the major reserves, but then you have smaller reserves held by other countries and individuals, and of course all the jewelry in the world. According to the BBC's online magazine, Science Focus, the World Gold Council reported in 2015, that there are around 184,000 total tons sitting in bank vaults, government reserves and personal collections, with jewelry accounting for roughly 50 percent of that number. That sounds like a lot of gold but as gold is so heavy, one cubic meter weighs over 19 tons. So all the world's known gold reserves could be laid out on a football pitch in a layer only a meter or so high. Is 184,000 tons all the gold in the world? Well not really. This is only the gold that has been successfully mined and is accounted for. Estimating how much actually exists on the planet is much trickier. Chemical analysis of rock samples suggests gold makes up on average a few parts per billion of the total mass of the Earth's crust. That means the top kilometer has around a million tons of gold still waiting to be dug up. But the chances of drilling deep enough to get your hands on it, are unlikely, as the cost of excavation would deem the process uneconomical. Bad economics were a bitter lesson for the brilliant German chemist Fritz Haber in the 1920s. After World War One, Germany were ordered to pay between 50 and 132 billion German gold marks to France, Britain, and Russia, as part of the 1919 Treaty of Versailles. This was a huge financial blow to the war-torn country. So Haber came up with what he thought was a genius idea by which to extract tiny amounts of gold from seawater. Seawater contains a smorgasbord of elements such as sodium chloride, potassium, and magnesium, and even uranium in trace amounts. Haber believed the gold within the world's oceans could be withdrawn and accumulated, and used to help Germany pay their debt. He estimated that 65 milligrams of gold could be extracted from one metric ton of seawater. Using massive centrifuges and his expertise in electrochemistry, Haber planned to separate the gold from the seawater. A process that would consume massive amounts of energy but if his calculations were correct, then this costly process would pay for itself. But Haber's calculations were not correct and he discovered that the concentrations were much lower than he had originally estimated. Each liter of seawater contained just 13 billionths of a gram of gold. Though we know what the banks hold in reserve, getting an exact number on the amount of gold that's in the world is not easy with personal reserves, jewelry, and more recently in nanotechnology where gold is increasingly being used in medicine, engineering, and environmental management in very small amounts. Gold has traditionally been considered a good investment as it maintains a stable value. Will the price of gold keep rising? The talk online seems to suggest that 2018 will be a good year, but what do you think? Let us know in the comments. Also be sure to check out our other video Most painful things a human can experience. Thanks for watching, and as always, don't forget to like, share and subscribe.