The painting, which features the same enigmatic smile as his Mona Lisa, was discovered in a Swiss bank vault — to the delight of the art world, many of whom had doubted its very existence.
It is a painted version of a pencil sketch drawn by da Vinci in Mantua in the Lombardy region of northern Italy in 1499.
The sketch — the inspiration for the newly found painting — hangs in Paris’ Louvre Museum.
The portrait — which was until now believed to have been either lost or never even painted — belongs to an unnamed Italian family which kept it in the vault of a Swiss bank along with 400 other works, Sette magazine reported. It measures 61 by 46.5 centimetres (24 by 18 inches) and depicts the prominent Italian marquess, who was a patron of the arts, in profile.
It is “a faithful transposition of the famous sketch hanging in the Louvre,” said Sette, which belongs to the Corriere della Sera daily.
It quoted Carlo Pedretti, a world expert in the Tuscan painter (1452-1519), saying: “I can immediately recognise Da Vinci’s handiwork, particularly in the woman’s face.”
Only around 15 works have been reliably attributed to Leonardo, including the “Mona Lisa” — the most famous and popular painting in the world.
Art historians long believed he simply ran out of time, or lost interest, in completing the commission for Isabella d’Este. Experts believe it was painted before the Mona Lisa.
The newly-found portrait has the same paint pigment and primer as those used by the artist in his other works.