Through interviews with gemstone cutters as they work, dealers at markets and through poetry, prose, stories and legends about them, 'Letting out the Light' reveals what has made mankind treasure gemstones throughout history.
Stephen Gill is a Sony Award-winning radio writer - and a gemmologist. His belief is that the processing of gems - cutting, grinding and polishing- is not to impose a beautiful shape but to 'let out the light' of the stone.
He has travelled from Japan to Sri Lanka and the United States listening to gem dealers and stone cutters, gathering their stories and the sounds of their work. Michael Dyber recalls working with a crystal weighing 26 kilos; we hear the history of the Chhatrapati Ruby, first documented in 380Ad; Nimal Pathirana tells the story of the sapphire in Princess Diana's engagement ring.
At the Tucson Gem and Mineral Show, the largest in the world, dealers and cutters praise their favourite stones: Zarin Gul, from the Swat valley, and Yoko Okubo, from Tokyo, love topaz; for Falk Burger it is aquamarine; for Wang Huiping, mountain quartz. At the gem auction in Ratnapura there is frenzied bidding for garnets, topz and moonstone
We hear poems inspired by gems, legends of their origin and cool scientific analysis - what aquamarine actually is, how iron lends hessonite its orange hue, why a crystal bowl sings.
Michael Dyber and Bernd Munsteiner, among the finest gemcutters in the world, saw, grind and polish. We hear how they let out the light, and we hear this happen.
Stephen Gill has gathered sounds, interviews, poems and stories, but, like a jeweller, does not himself appear in 'Letting Out the Light', a programme in which the elements, all different, are linked like a string of aural jewels.