Has another rare Black Sabbath recording from the metal legends' Heaven and Hell era with singer Ronnie James Dio surfaced? The family of late Sabbath member Geoff Nicholls has the goods.

A clip containing a purportedly unheard Black Sabbath tune with the presumed title "Slapback" emerged last week from Gary Rees, Nicholls' stepson and the executor of his estate, as Blabbermouth reported. The previously unreleased song from a 1979 rehearsal tape is said to feature Dio alongside classic Black Sabbath rockers Tony Iommi on guitar and Bill Ward on drums.

It's not known for certain who played bass on the recording, however, seeing as how Sabbath bassist Geezer Butler was absent for some of Heaven and Hell's early creation, Rees speculates in the description for the video that it must be "Ronnie on bass or 'a friend from Birmingham.'"

"I believe [it's] called Slapback from the scrawling on the cassette," he adds. "It doesn't sound like a typical Sabbath song if it is them, but it does sound like Ronnie James Dio. It must be a cover, any clues?"

In January, a previously unheard 1979 rehearsal take of Heaven and Hell's title track was unearthed that actually featured Rees himself on bass. He explained that he found the rarity on a cassette "amongst the thousands in Geoff Nicholls' archive. On the inlay card is written 'On & On Heaven & Hell Original Version Geoff Playing Bass.'"

Nicholls, who died in 2017, was a longstanding Black Sabbath contributor, although his role within the group was a shadowy one. He gets credit for performing keyboards on a total of 10 Black Sabbath albums — everything from Heaven and Hell through 1995's Forbidden — and he served as a live member on both keys and the occasional rhythm guitar.

Black Sabbath - Unreleased 1979 Rehearsal Recording From Geoff Nicholls

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