Commodities giant valued at £37bn as it mulls listing

That value placed on it by Liberum Capital would place it among the 15 biggest FTSE-listed companies if it were to secure a London listing. Barclays, ranked 15th in the FTSE 100, has a market capitalisation of about 36.3bn.

Glencore's estimated value has leapt about 22 per cent since July, when it was worth $49bn, according to Liberum Capital analysts led by Michael Rawlinson, a former banker at Cazenove and JPMorgan Cazenove who worked on the IPOs of Billiton, Xstrata, Vedanta, Anglo American and Kazakhmys.

The company's worth has been boosted by a surge in the value of its 34 per cent stake in Xstrata and other listed holdings.

Shares in the London-listed mining company have gained more than a third in the last six months.

The "sum of the parts" valuation suggests over a third of Glencore's value derives from its vaunted trading operation.

The Liberum analysts reckon that Glencore' trading business

is worth some $23bn, based on

the rising price-to-earnings ratios of smaller public peers such as Singapore-listed Noble Group Ltd.

Its stakes in Xstrata and other listed companies such as Century Aluminium, Minara Resources and UC Rusal are worth another $29.5bn.

Glencore's unlisted mining assets – such as zinc, copper, and gold mines – are worth another $14.6bn, with its coal business the biggest at $5.1bn.

The unlisted assets' value has fallen slightly, based on lower earnings multiples.

The analysts apply a 10 per cent discount to the whole to arrive at a $60.4bn equity value, or 37bn, and an enterprise value of $74 bbn including debt.

Glencore had revenues of $70bn in the first half of 2010.