Friends of Jean-Michel Basquiat are calling out Beyoncé and Jay-Z for their use of a painting by the late American artist in an ad for jeweller Tiffany & Co.

The new ad campaign features the music industry superstars modelling black formal attire and a yellow Tiffany Diamond in front of Basquiat’s 1982 painting Equals Pi.

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Alexis Adler, who was Basquiat’s former roommate, criticized the ad in an interview with The Daily Beast.

“I’d seen the ad a couple of days ago, and I was horrified,” Adler said. “The commercialization and commodification of Jean and his art at this point – it’s really not what Jean was about.”

He continued, “Unfortunately, the museums came to Jean’s art late, so most of his art is in private hands and people don’t get to see that art except for the shows. Why show it as a prop to an ad?”

Basquiat’s former studio assistant Stephen Torton also said, “They wouldn’t have let Jean-Michel into a Tiffany’s if he wanted to use the bathroom or if he went to buy an engagement ring and pulled a wad of cash out of his pocket.”

Tiffany executive Alexandre Arnault explained how the painting’s use of the brand’s trademarked shade of blue connects back to Tiffany, which now owns the portrait.

“As you can see,” he said, “there is zero Tiffany blue in the campaign other than the painting. It’s a way to modernize Tiffany blue.”

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But an anonymous curator of Basquiat’s paintings criticized the supposed connection of the blue in the painting to the Tiffany brand.

“Let’s say he did reference that colour on purpose—which seems out of character for him to do something that simple—I think it really flattens his artistic approach. He was a really deep thinker. His work wasn’t like, this symbolizes this. Everything references something but then it tells a story of that thing. But let’s say he did though… to use it in an ad, it wouldn’t have been the context. It wouldn’t be used to sell Tiffany’s but to say something critical, maybe about blood diamond-extraction or something. I just think it’s a reach.”

ET Canada has reached out to Beyoncé and Jay-Z’s reps for comment.