Ronnie James Dio: one of hard rock's definitive voices

For someone who always seemed to be just off to the side of the biggest stages in rock, the late Ronnie James Dio certainly inspired a lot of affection. He's best known, perhaps, for working alongside musicians much better known than him, and usually when those musicians appeared to have passed the peak of their own success. So he joined Ritchie Blackmore in Rainbow after Blackmore had departed Deep Purple. After three albums with Rainbow he replaced Ozzy Osborne in Black Sabbath, staying with them for two studio records before heading off to front his own band, Dio. In recent years there had been a reunion with Sabbath, under the name Heaven and Hell to avoid confusion with the Osborne-fronted Sabbath that was also touring.

So far, so upper-to-middling a rock career. But Dio was more than just a travelling vocal troubleshooter to heavy rock fans. For a start, he had one of the definitive hard rock voices, a rich baritone that could rise through the octaves. He didn't blur or spit his words, so you could hear everything he sang, which was crucial to his appeal. Dio perfected what many people see as the template of hard rock lyricism – swords, sorcery, wizards in towers, men on silver mountains, kings to be killed. It wasn't subtle, but Dio communicated as clearly with fans who read Stephen R Donaldson and Frank Herbert epics as Morrissey did with those who were watching kitchen sink dramas. It made him easy to parody – our band at school, 25 years ago, had a song that began: "In a mystical time/ before reason and rhyme/ When the blood stained the axe and the fire," which was the result of too much time spent listening to the first Dio album, Holy Diver. Jack's Black Tenacious D acknowledged the same feelings – a mixture of mockery, affection and slightly ashamed admiration – 20 years later, with a song called, simply, Dio.

So there's the voice, the lyrics, but there's something else, too, that places Dio in an exalted position in the great throne room of metal: his use of his index and fourth fingers. It was Dio who brought to hard rock the devil's horns, the international symbol of all thing's rockular, understood throughout the world and across generations. The sign of the devil's horns is a physical Esperanto more easily understood than any other gesture save, perhaps, the raised middle finger. To have brought that to the world is one of those ludicrous but endearing and enduring achievements that only metal can really manage.

If it sounds like I'm having a laugh at Dio's expense, I'm not. Because above and beyond those things, Dio sang on some extraordinary and unforgettable songs. Stargazer, by Rainbow, is for my money better than Led Zeppelin's Kashmir, a great song itself but overshadowed by the preposterousness of Dio and Blackmore's vision. His presence reinvigorated Black Sabbath into producing their best work in years – the likes of Heaven and Hell, Neon Knights and The Mob Rules stand as equal to anything from the Ozzy years.

I never saw Dio perform live and, now he has died of stomach cancer at 67, I never will. With a whole generation of rock stars from my youth now entering old age, metal is going to have get used to its heroes passing not in plane crashes, or from the effects of partying, or in other rock'n'roll ways. They are going to die of the things that kill ordinary people, a reminder that the swords and sorcery are not real, and that beneath the leather and the hair lurk real people who have sometimes, like Dio, done remarkable things.