Lance, that's a superb question. A brilliant chemist / inventor has developed a procedure in which a photographic emulsion can be non destructively removed from its original old paper and transferred to new material. I've seen samples of this terrific achievement at the Photography Department of the Musuem Of Art here in NYC. I can't recall the name of the vendor who developed the method, but certainly the curators there know. Even for disks that have broken into pieces, this might have important potential for retrieving sound from such broken & damaged media. Best, Shiffy