How to forge a masterpiece

1. GET THE RIGHT PAINTS

It’s fairly easy to analyse the paint pigments used in a picture and compare them with those in a known masterpiece, so knowing your paints is crucial. Regardless of whose work he was forging, Tetro knew what he had to buy. “I know Dali used Lefranc [& Bourgeois] oils when he painted in Europe, and Grumbacher oils when he was in the US – he often wintered in New York.”

2. GET THE OTHER MATERIALS RIGHT

If it was a Dali, Tetro could buy a new canvas and age it himself (see 4 below). If it was an old master, it was better to get an old picture and strip it with paint remover. To get one canvas exactly right (it needed to be from Monmatre in France and date back to the 1920s or 1930s), he paid $7000 for a picture before stripping off the paint. “That painting could be worth hundreds of thousands of dollars today. It wasn’t that good anyway.”

3. PAINT THE RIGHT SCENE

If you’re out to create a previously undiscovered classic, it’s worth researching the paintings of the same artist and the same era – then use similar themes. Getting the texture right is important too. Dali for instance painted with no texture – the brushstrokes often aren’t visible and the texture of the canvas itself is visible. As for the artist’s signature, “It has to be fluid,” says Tetro. So practice makes for a convincing scrawl.

4. AGE THE PAINTING

Ageing the canvas starts by applying diluted bleach to the back to make it feel old and brittle. Then a concoction of umber (brown paint) diluted with thinner and the liquid from cigarette butts soaked in water is rubbed into the back of the canvas and the surrounding wood. “I wouldn’t mind if the painting got scratched and damaged, remember it’s old.” The front is aged with a 70/30 blend of thinner and umber blend.

 5. ADD 'CRACKULAR'

It normally takes 50 years for cracks to appear in a painting. “It adds a ton of authenticity to it. A lot of this is psychological – you’ve got to make ’em think they’re looking at something that’s been around for a while.” Tetro mixed oil and water-based liquids that cracked when applied to a painting together. A thin layer of umber was then applied and wiped off – it filled the cracks, looking like dirt. Finally, it was just a case of applying a varnish.

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