I totally stumbled across this on YouTube:
It is Jean Cocteau's version of Beauty and the Beast but dubbed (yes!) to Philip Glass' opera. Utterly amazing (and Belle is SO beautiful in the film!!) A friend actually lent me the black and white feature on DVD but my computer is regionally locked so can't play the disc. Just as well. What a surprising and great find. Will watch it now.
Meanwhile, have bought this really old Nokia on eBay (8310!) ... hope it still works!!