A Da Vinci sketch the size of a Post-It Note just sold at a Christie's auction for $12 million

• A tiny Da Vinci drawing fetched a big price of $12.2 million at a July 8 Christie's auction.
• The sketch, "Head of a Bear," measures only 2.75-by-2.75 inches.
• It is one of the painter's studies of animals, and experts believe the piece came from Da Vinci's sketchbooks.

Would you pay over $12 million for a drawing the size of a Post-It Note? The answer for one art buyer was a resounding yes.

The drawing was a sketch from Leonardo da Vinci, and one of the rare sketches from the Italian Renaissance master to hit the auction floor in the last 20 years.

Titled "Head of a Bear," the piece was created using a technique called silverpoint, which involves artists employing a thin, silver wire held on a makeshift stylus to make etchings on paper.

This tiny 2.7-by-2.7-inch sketch was auctioned off for $12.2 million to an unknown buyer at Christie's London on July 8, under the auction house's "The Exceptional Sale." Christie's did not immediately respond to a request for comment from Insider on the identity of the piece's buyer.

"The drawing was executed in silverpoint on a pale prepared paper, an incisive and demanding technique which Leonardo was taught in his youth by his master Andrea del Verrocchio, the leading artist in Florence at the time," Christie's wrote in the piece's auction listing.

Christie's noted that its small size aside, the sketch is"an exquisite demonstration of Leonardo da Vinci's unsurpassed mastery as a draftsman and of his ground-breaking attitude towards the study of nature."

According to the auction house, "Head of a Bear" is one of fewer than eight drawings by da Vinci that are still in private hands and not in the possession of museums.

The auction house also noted that the piece had a "distinguished provenance," having previously been in the private collection of British portrait painter and collector of old master drawings, Sir Thomas Lawrence. Interestingly, the sketch was sold at Christie's way back in 1860 for just 2.50 pounds ($3.40), equivalent to around 311 pounds ($428) today.

"I am delighted that this masterpiece, one of the most important works from the Renaissance still in private hands, has once again been entrusted to Christie's after its first sale in 1860," said Ben Hall, chairman of the old master paintings department at Christie's New York in a press release. "It has been admired around the world whilst shown by prestigious museums, and Christie's is honored to bring this Leonardo to the market this season."

Da Vinci's drawings are rarely ever auctioned. The last one seen at an auction was "Horse and Rider," a 4.72-by-3.06-inch silverpoint study of a horse between two trees. This piece was sold at Christie's back in 2001 for $11.2 million.

Yet this is far from the highest price a da Vinci masterpiece has fetched at auction.

In 2017, the painter's "Salvator Mundi" (or "Savior of the World"), a portrait of Jesus Christ created around 1500, was sold for $450.3 million at Christie's in New York City. This is to date the most expensive piece of art ever sold in an auction.