Ozzy Osbourne has death on his mind. As a self-confessed hypochondriac, this isn’t unusual. But for once, it’s not his own mortality that’s bothering him.

“Fucking hell, man,” he mutters. “I just heard about Prince. Dead. The papers are saying he OD’d.”

His eyes visibly widen behind his round, Lennon-esque shades. “Fuck me. It’s been a shitty year. People keep dying. Every other week some other c**t dies.” He shakes his head, looking simultaneously rueful and befuddled in the way that only Ozzy Osbourne can.

It’s lunchtime in Sydney, Australia. A few hours earlier, the country woke up to the shock news of the Purple One’s death. The Grim Reaper has delivered another rabbit punch to rock’s already battered psyche. Lemmy, Bowie, Dale ‘Buffin’ Griffin, Glenn Frey, Jimmy Bain, Keith Emerson and now Prince. You can’t help wondering when it’s going to stop. Especially if you’re Ozzy.

“Lemmy, man,” he says. “That broke my heart. If someone was to say to me, ‘What’s your depiction of the heavy metal rock star?’, I’d say Lemmy Kilmister. He always said, ‘I’ve lived my life the way I want to. I may have been able to live to eighty if I hadn’t smoked, or drank Jack Daniel’s, or done speed, but fuck that.’ Saying that, I bet if he had a fucking chance to come back and be around for a few more years, he fucking would.”

The two of us are sitting on adjacent-but-one chairs at a polished round table in a tastefully appointed room in one of Sydney’s more discreetly upmarket hotels. From the ankles up, Ozzy looks exactly as you’d expect him to. Black T‑shirt, black trousers, thicket of hair framing those sunglasses, their purple lenses inadvertently appropriate today.

It’s only when you look down that the rock star illusion is shattered. Ozzy’s feet are stuffed into a pair of fetching blue and purple hotel slippers, which carry him around in that unmistakable hunched-over, sped-up shuffle. But then he is 67 years old, and if a 67-year-old can’t pad around in slippers, then who can? Especially one who has come close to dying more than once.

“Oh, fucking hell have I. Just ask my family. I’ve nearly died loads. I’ve had several stomach pumps, my heart stopped twice when I broke my neck on a fucking quad bike. Every time I got stoned and drunk, I didn’t get tipsy I got fucked. I haven’t drunk for three years, I haven’t smoked for twelve years, I don’t do drugs any time. It’s cool.”

So you aren’t planning on departing us yet?

He grimaces a cartoon grimace. “Fuck that. Sharon told me: ‘You’re not fucking going anywhere till this tour’s finished.’”

For Black Sabbath, matters of age and death are more pertinent than they’ve ever been. Their current world tour, bluntly titled The End, is billed as their swansong. Just as the five dates they are playing in Australia will be their last time in this part of the world, so their headlining slot at the Download festival on Saturday, June 11 will be their final appearance in the UK.

As it stands, when the tour ends in Brazil in December, Black Sabbath will cease to exist. Thank you and goodnight, that’s your lot. Would the last one out please turn off the lights. And you don’t know it yet but, like Lemmy, like Bowie, like Prince, you’ll miss them when they’re gone.