I have several white cotton pillowcases--the old embroidered stuff, a lot of which is good grief 60-70 years old--that I stupidly washed a few times in my rusty well water(not there anymore, on city water now). There is that dingyness I can't get out yet--don't want to bleach the heck out of them. SO any tipes to get them nice and white again? Or just use dim lightbuls in the bedroom ha!???