Before it evolved into the blues covers set Blue and Lonesome, the Rolling Stones' next studio album was supposed to contain new original material. What's going on with that project, and when will fans be able to hear it?

As the band explained in a new profile piece in The New York Times, the record took a turn when they showed up at Mark Knopfler's British Grove Studios. The room they'd booked was outfitted with a Decca tree — basically a tall overhead mic array — and it prompted some conversation about how to best record the new material from an engineering standpoint.

While things were hashed out on the technical front, Keith Richards decided to stay busy by working up a cover of Little Walter's "Blue and Lonesome" — a song he'd earlier told guitarist Ron Wood to learn as a reference point for what he was hoping to get out of the new material. Describing the band as "a little unsure of the studio and the sound of it," Richards recalled, "I looked at Ronnie and said, ‘Let’s put a hold on this new stuff while we try and figure things out and get the room warmed up. Okay.: ‘Blue and Lonesome.’"

That impulsive decision inspired singer Mick Jagger, who called up a Howlin' Wolf song as their next number, and by the end of the day, they had five tracks committed to tape. The end result is a record drummer Charlie Watts describes as "what I've always wanted the Stones to do" — but it begs the question of when the band might get around to finishing those new originals.

The answer, it seems, won't be revealed anytime soon. Jagger told the NYT that they only have "half an album" of material — and Wood hinted that those songs may need quite a bit of time in the studio before they see release.

"It’s like putting it on top of the strainer and seeing what soaks through by the time you come back to them again," said Wood. "The lumps that are left on top after time has gone by, that’s what you make your dough out of. It wouldn’t surprise me if we recut them all again. It’s one of those things."

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