The Rolling Stones' first new, completely original album in 18 years will be out next month, and it has a star-studded guest lineup. Pop superstar Lady Gaga is one of the artists who makes an appearance on the album, and her background in rock 'n' roll makes her a great fit.

Paul McCartney, Elton John and Stevie Wonder all made contributions to the album as well, which is titled Hackney Diamonds. Lady Gaga sings on the song "Sweet Sounds of Heaven," which also features keyboard contributions from Wonder. Mick Jagger told the Associated Press that the pop singer was recording in a Los Angeles studio next to the Stones, and was invited to collaborate with them after she went in to say hello.

“She walked in next to me and we started singing together,” the frontman said. "She sang it live and then we went in and tidied it up a bit.”

Years before she became a megastar, Gaga played in cover bands in New York City that primarily covered Led Zeppelin [see a clip of her singing 'Black Dog' below]. She's also praised Iron Maiden as one of the most important musical groups in the world, and said that they changed her life.

"Some people really don't know the importance of metal and the scope of it. Those guys were filling stadiums, and they still are," she told CR Fashion Book [via Independent]. "And it's because of the culture of the music, the poetry that's so powerful, that whenever the fans come together they unite in the essence of what Iron Maiden is all about. I always used to say to people, when they would say, 'Oh, she's the next Madonna.' No, I'm the next Iron Maiden.”

As for the other collaborations on Hackney Diamonds, McCartney played bass on the song "Bite My Head Off" and John played piano on "Live by the Sword." You can see the full album details and track listing here.

Hackney Diamonds was produced by Andrew Watt, who's really dipped his feet into the world of rock and metal over the last few years by working with other huge names such as Ozzy Osbourne, Iggy Pop and Pearl Jam. While the first song they shared from the set, "Angry," has a classic Stones sound to it, Jagger added that there are also “love songs, ballads, country-type” tracks throughout the record.

“I don’t want to be big-headed but we wouldn’t have put this album out if we hadn’t really liked it,” he asserted. “We said we had to make a record we really love ourselves. We are quite pleased with it, we are not big headed about it, but we hope you all like it.”

READ MORE: See Mick Jagger's 6-Year-Old Son Dance at Guns N' Roses Show

The album technically serves as a follow-up to 2005's A Bigger Bang, as their 2016 release Blue & Lonesome was comprised solely of blues covers.

“When you have a singer that wants to sing, you grab him and throw him in the studio,” Keith Richards said, noting that the gap between their albums was mostly Jagger's decision.

Hackney Diamonds will be out Oct. 20. You can pre-order it at this location.

Lady Gaga Sings Led Zeppelin's 'Black Dog'

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