Nearly every chief executive and chief financial officer that Ian Hannam had worked with in the previous 20 years turned up for his leaving drinks last summer, according to attendees. The standard speech was delivered not by a JP Morgan colleague, but by Mick Davis, chief executive of mining giant Xstrata and a long-time client.

Hannam was leaving to fight a fine levied by the Financial Services Authority for market abuse relating to client Heritage Oil. At the time, Davis, Martin Gilbert of Aberdeen Asset Management, and David Davis, the former Tory leadership candidate, all spoke out in support of him. And, given his standing in the market, few expected the JP Morgan banker and former captain in the British Territorial Army to be out of the game for long. Indeed, his exit set off a spate of speculation as to what the so-called "King of Mining M&A" might do next, and which of a cadre of former colleagues might be involved. If the past is any guide, the group is unlikely to disappoint.