I have recently bought my wife, Karen, a pair of Christian Louboutin Cork Platform Sandals (Marpoil Sanpla Sughero). They are not new but are in generally good condition. The cork is all good but could do with some cleaning at one or two places. They are not badly stained but just show some darkening here and there. So how do you go about cleaning the cork facing on CL sandals? Also, once clean what do you apply to them to keep them that way? Any advice gratefully received.