I have never used color to fill in headstamps but getting older they are hard to read. I have seen various colors used at this. What do people use to fill in these headstamps ?
White or color chalk
Does chalk last ?
No, t6he chalk does not stay in very well. It is fine for taking a photo of a headstamp, but use a white grease pencil or crayon (anything with a wax base) for more permanent fill, but can be easily removed if wanted with a tooth brush.