The portrait was made using ink, canvas and an artificial intelligence algorithm, and was signed with a math equation.

And while Christie's expected the A.I.-created portrait to fetch $7,000 to $10,000, on Thursday it sold for $432,500 — over 40 times the initial estimate — to an anonymous bidder.

"Edmond de Belamy, from La Famille de Belamy" is no ordinary piece of art. It's the first portrait generated by an algorithm to be sold by a major auction house.

"We gave the algorithm 15,000 portraits and the algorithm understands what the rules of the portraits are, and creates another one," Pierre Fautrel, co-founder of Obvious, the art collective that created the work, previously told CNBC Make It.

The goal of the painting and of Obvious, also co-founded by Hugo Caselles-Dupré and Gauthier Vernier, was to prove "artificial intelligence can do more than operate driverless cars or transform manufacturing — it can be creative," CNBC Make It reported.

Portraiture is a tough genre for AI to take on, according to Christie's, "since humans are highly attuned to the curves and complexities of a face in a way that a machine cannot be."

This difficulty was part of Obvious' thinking when they created the portrait.

"We did some work with nudes and landscapes, and we also tried feeding the algorithm sets of works by famous painters. But we found that portraits provided the best way to illustrate our point, which is that algorithms are able to emulate creativity," Caselles-Dupré said.

"Edmond de Belamy" is one of 11 AI paintings made by Obvious.

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