5. Codex Leicester

Bill Gates bought the Codex for $30.8m, making it the most valuable manuscript in the world

To this day, Leonardo Da Vinci's Codex Leicester remains the most valuable manuscript ever sold, after it was bought by Bill Gates in 1994 for $30.8m. Long before Gates' record breaking purchase, however, the manuscript appeared at Christie's on December 12, 1980. It was offered from the private collection of Lord Coke, who claimed he had been forced to sell the precious document in order to settle what must have been an absolutely enormous tax bill.

The document was given a top-end estimated valuation of $20m but bidding opened at just $1.4m and, by all accounts, lasted less than two minutes. The Codex was bought by the American oil tycoon Armand Hammer for the somewhat lowlier figure of $5.1m - reportedly not quite enough to cover Lord Coke's tax bill.

4. Horse and Rider

 

Da Vinci's horse and rider sketch sold for $11.5m in 2001

Leonardo Da Vinci's Horse and Rider sold at Christie's in London for £8.1m ($11.5m) in July 2001. The silverpoint study of a horse emerging from between two trees is thought to be one of Da Vinci's preliminary sketches for the unfinished work, Adoration of the Magi. The picture is believed to have been commissioned by the Church of San Donato a Scopeto. It was left unfinished when Da Vinci left Florence for Milan in around 1482.   

3. Jeanne Marchig's "German School, early 19th century"

The sketch caught the eye of art historian Martin Kemp who identified it as a Da Vinci

In 1998 Jeanne Marchig sold an unassuming portrait, supposedly of German origin, at Christie's New York for $19,000. The chalk, pen and ink sketch on vellum, however, caught the eye of art historian Martin Kemp, who posited that A young Girl in Renaissance Dress, as it was also known, was neither German nor 19th century, but a bona fide Leonardo Da Vinci original.

Carbon dating confirmed that the painting was probably created during the 15th century and the estimated worth of the work duly increased by a factor of over 1,000.

A federal judge dismissed the law suit filed by Marchig against Christie's for misrepresenting the work, because the statute of limitations deems that no more than three years may lapse from the time the alleged infraction occurs.

2. The Mona Lisa

Da Vinci's most famous and celebrated work, The Mona Lisa, holds the world record for the highest known insurance valuation given to any painting

The world's ultimate collectible?! The Mona Lisa holds the Guinness world record for the highest known insurance valuation of any painting. When, in 1962, a special exhibition of the painting was suggested, Washington and New York seemed like suitable destinations. An insurance assessment was made, taking into account travel from the Louvre and across the USA, and a valuation of $100m placed on the painting. The insurance was never finalised, however, as the cost of the most thorough security precautions turned out to be a great deal less than the cost of the premiums.    

1. The Battle of Anghiari

The Battle of Anghiari (or "the lost Leonardo") is regarded as one of the great remaining mysteries of the art world. This year, rumours of the mural having resurfaced emanated from the Palazzo Vecchio in Florence, where Da Vinci is believed to have completed the painting in 1504. Its "discovery" has sparked much conflict and controversy between experts, many of whom believe the newly uncovered painting is the work of an inferior artist.

Officially unseen since 1555, the fresco is an inherently mysterious art work, which may or may not still be in existence.