To start with, Martin Kober's claims met with not just raised eyebrows but full eye-rolling. Not that it was ever thought to be impossible for an undiscovered Michelangelo to turn up in a sitting room a little way to the north of Buffalo, New York, but it didn't exactly seem like a safe bet.

The world is not short of 'possible' Michelangelos. In recent decades they've been showing up at the rate of two per year, and the old master might have had a terrible case of tennis elbow if he'd painted them all.

In December last year, we referred to the row over a sculpture of the crucifixion supposedly done by Michelangelo and bought by the Italian government for €3.3m, which then had its authenticity questioned by some experts.

Traditionally, the Kober family has always regarded the painting which hung behind the sofa in their living room as a Michelangelo, even referring to it as 'The Mike', though didn't stop them exercising their own 'tennis elbows' - the work took a gentle thwack from a tennis ball on at least one occasion.

But retired Air Force Lieutenant Colonel Martin Kober thought it was worth some research, and put a lot of effort into tracing a timeline back for the piece.

He believes it once belonged to a German baroness, who left it to one 'Gertrude Young', her lady-in-waiting. Young had sent it to the US for her brother-in-law, who turns out to be Kober's great grandfather.

Renowned art historian Antonio Forcellino is one of those who has been won round and now says that the work is definitely a Michelangelo. This follows a trip to see the painting for himself - which he believes could only have been created by a genius - and much more research.

The paper trail from studio to Buffalo is now complete, whilst infrared light, X-rays and chemical pigment analysis, have all been brought in to support the case for the panting's authencity.

The work is an unfinished Pieta, that is, a depiction of the crucified Christ in the arms of his mother Mary, which Forcellino believes was painted in 1545 - a time of Reformation in the Church.

Some experts have given estimates of $100m-300m for the work, if genuine. Regular readers will recall that modern techniques have also suggested that a work thought to be a minor German work appears to have Leonardo da Vinci's fingerprint on it, and that too could be worth a nine-figure sum.

Naturally if either is offered for sale, we'll be on the case.

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