Geoff Nicholls, who played keyboards with Black Sabbath from 1979-2004, has died. He was 68.

According to Tony Iommi’s post on Facebook, the cause was lung cancer. “I'm so saddened to hear the loss of one of my dearest and closest friends Geoff Nicholls,” he wrote. “He's been suffering for a while now with lung cancer and he lost his battle this morning. Geoff and I have always been very close and he has been a real true friend to me and supported me all the way for nearly 40 years. I will miss him dearly and he will live in my heart until we meet again. Rest In Peace my dear friend.”

Bassist Geezer Butler also shared his thoughts, writing, “Very sad to hear of old friend and Sabbath keyboard player Geoff Nicholls passing. RIP Geoff.” Ozzy Osbourne also offered his condolences, tweeting, "Geoff Nicholls was a great friend of mine for a long time. He will be greatly missed. I'm very saddened at the news."

Born in Birmingham, England on Feb. 28, 1948, by the mid-‘70s, Nicholls was playing guitar and keyboards in Quartz, whose 1977 debut was produced by Iommi. During that period of late-‘70s turmoil where Ozzy Osbourne was fired and Geezer Butler quit, Nicholls was hired as a bassist. But Butler’s return saw him switch to keyboards, and, under new singer Ronnie James Dio, released Heaven and Hell in 1980.

Despite numerous lineup changes and dwindling sales through the ‘80s, Nicholls stayed with Black Sabbath, becoming a full-fledged member beginning with 1986’s Seventh Star. During the ‘90s he was twice demoted, during the 1992 Dehumanizer reunion with Dio and Osbourne’s return in 1997. The 2004 arrival of Adam Wakeman, Osbourne’s keyboardist from his solo band, ended Nicholls’ time with Black Sabbath.

Following his departure, he worked with another Black Sabbath alum, singer Tony Martin, in his band Headless Cross, which was named after Sabbath’s 1989 album.

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