Gold is much scarcer than most people realise. If you gathered together every single ounce that has been mined during the past 10,000 years of human civilisation and melted it into a single cube, it would stand only about as tall as an eight-storey building. And, if no new discoveries are made, the world's gold mines will be empty in about 10 to 15 years.
Unlike most other commodities, this scarcity plays a big role in underpinning the value of gold, which is why investors have been buying it in record numbers since the start of the financial crisis. In a normal year more than half of all the demand for gold comes from jewellers,...