From: Roger Kulp <[log in to unmask]> > Could someone tell me why the surfaces of so many Diamond Discs seem > to flake and peel off,leaving the core exposed? Roger This was a problem in the earlier years because the surfaces were a celluloid sheet laid on a wood-flour core. The wood-flour core would absorb water which is why Edison discs must NEVER be washed. The rims start to spread and separate, and the celluloid will curl. The three dimples in the label area were supposed to help keep the celluloid layer secure, and they continued to have the dimples in later years when the top surface was changed to a liquid called Condensite which hardened with the pressure of the press with pressing times between 20 and 40 minutes. The core material became changed to clay which did not absorb water. This started during the war years when quality materials were scarce, and the surfaces were not quiet for several years. It was finally when they started using the paper labels in the early 20s that the disc surfaces became quieter. Mike Biel [log in to unmask]