[SyrNy1960]

Not sure if anyone has ever used this stuff, but it works great. It won't damage your card (well, I never had it happen. Always used a cheap stained card first to test it). I purchased many cards (50's, 60's and 70's) with stains, soaked them (individually) in a sealed-tight container for a bit, then once you open the container, you will see the liquid quickly evaporate on the card. Didn't always work (depending on what the stain is), but it most cases it did work.