Ivan Glasenberg
Glencore chief executive Ivan Glasenberg's personal fortune has endured a torrid year in 2015Reuters

Anglo-Swiss commodity trading and mining giant Glencore recently saw its stock plunge 29% in one day, hitting a record low. Its stock has fallen by more than 85% since it went public in 2011, with over $52bn (£34.4bn) of shareholder value vanishing.

Glencore is saddled with debt and a key concern is that the $30bn load is simply too big to endure a continued slump in commodity prices. In recent weeks, the company's chief executive Ivan Glasenberg has sought to alleviate billions of dollars of debt by selling shares and assets and shelving dividends. Indeed Glasenberg himself wrote out a cheque to the tune of £138m, but who is the man who became a paper billionaire from Glencore's 2011 IPO?

Born in South Africa, Glasenberg grew up during Apartheid and went on to earn an MBA from the University of Southern California in 1983. He joined buccaneering Marc Rich & Co (Rich was charged with tax evasion and illegal deals with Iran but later pardoned by US president Bill Clinton), Glencore's predecessor firm in 1984 where he started as a coal trader. Following the buyout, he became the latter's chief executive in 2002.

A former race-walking champion who runs and swims daily to maintain his fitness, Glasenberg has a reputation as a workaholic with a fiery temper, at ease with the global uber-elite but also with a common touch willing to talk "to the guy on the trading floor". When Glencore listed in May 2011, Glasenberg became a multi-billionaire on paper, with his stake worth nearly $10bn. When he debuted on Forbes' Billionaires List in March 2012, his net worth stood at $7.3bn.

As Glencore's shares went into freefall on 28 September, Glasenberg lost more than 25% – or $500m – of his fortune in a single day, according to Bloomberg.

Since January 2015, the chief executive has lost 74% of his net worth. Following the listing in 2011, Glasenberg was ranked 301st on Forbes' rich list. He has since fallen more than 1,000 places to 1,335th. In spite of the figures, several of Glasenberg's colleagues have had to swallow far more bitter pills since the shares tanked, with Forbes estimating the relegation of Daniel Mate, Aristotelis Mistakidis, Tor Peterson and Alex Beard from the 10-figure club.