PAINSTAKING work will be carried out on a spectacular oil painting of Rome's Colosseum to find out if it is the work of Derby's Joseph Wright.
If it is proven, the value of the piece, in the collection of Derby Museums Trust, would rocket from being worth hundreds of pounds to tens of thousands, according to a leading auctioneer.
And no matter what the outcome, the piece, called the Colosseum by Moonlight, will go on display at the city's museum for the first time, alongside its companion piece – proven to be a Wright – the Colosseum by Daylight.
The painting has been in Derby since 1960 but experts are only now able to carry out the investigation, thanks to a £15,000 grant.
Lucy Bamford, senior curator of art at the trust, said it was a "really exciting time".
She said: "It's always exciting to do conservation work on a Joseph Wright or any other painting in the collection because you never know what it will uncover.
"I think it's unlikely that it will turn out not be a Wright, given what we know about it, but if it does the question becomes who painted it and why because it's being touted as something that it isn't."
No other examples of Wright's Colosseum paintings are known to have survived, though his account book lists four.
It arrived damaged and was sent off for conservation work that saw it almost completely over-painted.
That left experts unable to confirm whether it was a Wright without the use of the techniques art conservators have available to them today.
Meticulous work should now mean they can remove part of that top layer of paint to see what lies beneath.
First, infra-red lights will be used to see where the alleged Wright paintwork starts and the 1960s conservator's begins.
Then the layer will be slowly removed under a microscope using specialist chemicals.
What is revealed will then be compared to the Colosseum by Daylight and other Wright pieces to check if it is the work of Derby's most famous artistic son.
The investigation is only possible thanks to the £15,000 grant from The Pilgrim Trust, which aims to preserve and promote Britain's historical and intellectual assets.
Trust executive director Tony Butler said the grant would pay for the majority of the work.
News of the investigation comes after the trust discovered it was set for a major hit to its funding from Derby City Council as it looks to save £22 million in the next financial year.
Mr Butler said: "It wouldn't have been possible to spend £15,000 of our budget on something like this. We are trying to be more entrepreneurial, getting funding from a whole range of sources."
Prior to the museums trust taking over the running of the city's museum, the Silk Mill, and Pickford's House, in October 2012, the city's art collection was under the control of the council.
As a trust it has been more able to apply for grants, like the one for the painting work, than the authority would have been.
Mr Butler said it would be difficult to say what the value of the Colosseum by Moonlight would be if it was proved to be a Wright.
He said: "That's a matter for the arts market more than anything else. These things are only as valuable as people are prepared to pay for them."
Auctioneer Adrian Rathbone, associate director at Hansons Auctioneers, Etwall, said: "A painting following the style of Wright recently sold for £600. But a moonlight painting attributed to Wright, which was sold in Sussex, in April 2013, had an estimate of £70,000 to £90,000 and sold for £135,000."
Mrs Bamford said Wright's biographer and cataloguer, Benedict Nicholson, had given the trust reason to be optimistic about what the outcome of the painting work would be. She said he appeared to have seen both the Colosseum paintings before they were restored and that he believed them to be by Wright.
But Mrs Bamford sounded a note of caution as to what could happen when the work begins.
She said: "We have no way of knowing for sure, even with the modern analytical techniques, what sort of state Wright's original painting of the Colosseum by Moonlight will be in.
"Other paintings restored around the 1950s/60s have been discovered to have been sanded and scrubbed so as to give a smooth surface on which the restorer could lay new paint. "Conservation science was in its infancy, and a favoured approach was often to simply paint over the existing picture so as to 'improve' the appearance of it and make it displayable."
