On Friday 13 February 1970, Black Sabbath released their first album and a new genre was born - heavy metal.

On Friday 13 February 1970, Black Sabbath released their first album and a new genre was born - heavy metal. Witness speaks to guitarist Tony Iommi about the band's origins in Britain's industrial West Midlands - and the day his career nearly ended when he lost the tips of two fingers in a metal-working accident.

(Photo: Black Sabbath backstage at Top of the Pops (BBC). From left: Bill Ward, Ozzy Osborne, Tony Iommi, Geezer Butler)