Black Sabbath bassist Geezer Butler has been speaking to Revolver Magazine (via NME) about his reaction to guitarist Tony Iommi's lymphoma diagnosis. Butler revealed that the news had prompted him to write a song, tentatively titled Hanging by a Thread: "It was very much about dying, about giving your last breath and passing your spirit on. But the track didn't make it on the band's comeback album '13.' We never came up with the finished thing." Butler also noted that the feared the worst for Iommi because of his experiences with former Black Sabbath frontman Ronnie James Dio's death from cancer in 2010: "We didn't know if he (Iommi) was going to recover from it, especially after seeing Ronnie go so fast. Ronnie went right in six months from being diagnosed to dying." Ozzy Osbourne recently confirmed that he is intending to record another album with Sabbath, stating that he is "back" with the group for good.