While 15th Century artist Leonardo da Vinci painted many masterpieces, including the 'Last Supper, which depicts the final meal Jesus shared with his apostles before his crucifixion, he is most famous for a small 77 cm x 53 cm painting that sits encased in bulletproof glass at the Louvre Museum in Paris - The Mona Lisa! Now, it turns out that she may have some competition - A younger, happier version believed to have been painted by the Renaissance artist sometime between 1410-1455.

Named after the London suburb where British art collector Hugh Blaker discovered it shortly before World War 1, the Isleworth Mona Lisa is slightly larger than the iconic Paris version that attracts over 6 million visitors every year. But the resemblance to Lisa Gherardini AKA Mona Lisa is unmistakable, except for one thing - She looks a lot younger and happier!

The first person to suggest that it may be a genuine Da Vinci was Hugh Blaker's stepfather John Eyre, who in 1915 wrote a long essay about his theory. This view was reinforced in 1966 by American collector Henry F. Pulitzer, who bought the painting from Mr. Blaker. However, very few people took it seriously. When Mr. Pulitzer passed away he left it to his girlfriend who tucked it away inside a Swiss vault, where it lay for about 40 years.

Following her death in 2008, the painting was acquired by an International consortium of unnamed individuals who finally on September 29th, 2012, decided to ask experts to irrefutably prove that it was indeed, an earlier version of Mona Lisa - One that Da Vinci had handed over to Lisa Gherardini's husband Francesco di Bartolomeo, who it is believed had commissioned it as a gift for her birthday.

As would be expected most people were convinced it would prove to just a very well done forgery. After all, Mona Lisa fakes are constantly popping out of the woodworks and this one seemed to have a glaring flaw - Da Vinci's medium of choice was primarily wood, whilst this one was painted on canvas.

But after almost five months of tests that included one by a specialist in sacred geometry, as well as, brush stroke analysis done by experts from the Swiss Federal Institute of Technology, on February 13th the owners of the Isleworth Mona Lisa were proudly able to declare that this was indeed an original Da Vinci creation. We wonder what museum this version will star in.

Resources: guardian.co.uk,newsfeed.time.com,.huffingtonpost.com,news.discovery.com,nola.com