If princess Diana says it's a Banksy, it has to be a Banksy.
The princess's image is on the torn fake £10 note featured on the certificate that authenticates the first Banksy artwork to be auctioned in Africa. It is this unusual proof of authenticity that will push the price of the piece, entitled Flying Copper, to between R200000 and R350000.
The serigraph by the British street and graffiti artist goes under the hammer at the Stephan Welz & Co Fine Art and Collectables Auction in Cape Town on October 28 and 29.
It is one of 150 prints of the work, which he made in 2003.
Banksy hides his true identity but over the last decade has made a name for himself through his satirical graffiti, which has popped up in cities around the world.
His work has become highly sought after and originals can go for millions.
Banksy is believed to be worth R200-million.
That torn fake £10 note, explained Gary Shean, head of the Cape Town Stephan Welz & Co painting department, is a typical authentication certificate, issued by Pest Control, the company that sells Banksy's art.
Flying Copper was "a satirical contract between what is associated with happiness, the smile, and the starkness of militarised control", explained Shean.
The Banksy is not the only piece of high-end art to be auctioned.
Also on offer is the work of another street artist, Mr Brainwash. His signed work Madonna, one of a series of celebrity portraits, is believed to be valued at between R250000 and R350000. Local art on auction includes Walter Battiss's recto verso (two-sided) painting The Yellow Feather, recto Six Roosters valued at R700000 to R1.2-million.