I have a small Diamondbrite chip -- about the size of a Quarter and maybe 1/4" or less deep in the center and less deep around the edges. There is something dark in the middle of it... which I can't determine what it is.
Is there a good and easy (I know, not usually two words you use together) to fix this? Something like a hydraulic cement, except for this application (that can be used underwater... epoxy?)... Any ideas?