Soaking To Get Stamps Of Paper !! What Did I Do Wrong????

I am wondering what I did wrong! I separated my whites and colors and soaked them in lukewarm water, they came off easily after a while and I let them to dry on some inkless paper. I noticed the stamps which were pink ran off some color. These were the Abraham Lincoln 4 cent stamps. Has anyone else experienced this??? How can I avoid this in the future? Thanks
Ann

In general, one should soak on-paper stamps with cold (or room temperature) water. Depending on your water supply, sometimes you can get away with using lukewarm water, but in general you should avoid it as much as possible. Most water supplies will contain enough chlorine (and associated) ions so that the lukewarm water ends up acting like a mild bleaching agent.

If for some reason you must use lukewarm water (e.g., for some self-adhesive stamps), then you want to minimize the soaking time as much as possible. But in general, there is really no need to use anything but normal cold water.

agreed, cold water works best

I'll take this opportunity to also point out, that some stamps/paper will "run/ruin" even in cold water. These are few and far between, but I think worth mentioning...

1. Any color labeled "fugitive" or "fugitive ink" in the catalogs should NEVER be soaked directly in water. The ink dissolves in water. Other methods must be used to remove these stamps. However, these stamps are very uncommon and most of them are earlier issues.

2. Hologram stamps usually do not do well with soaking. If you must soak them, minimize soak time and blot/press them dry. Otherwise, some holograms will crack/flake.

3. Don't soak stamps on holiday-colored envelope paper (e.g., red, pink, green, purple...). You should either leave them on paper or junk them. The stamps won't run, but the envelope color will bleed onto the stamp, and sometimes onto other stamps.

4. Yes, there are some stamps that will color bleed very slightly even in cold water (e.g., 15c Edith Wharton stamp of the US). These are also very uncommon, but certain "purple" inks seem to be susceptible to this problem. On those stamps, soak separate from main batch and minimize soak time.

These are just some of the unusual cases I can think of off the top of my head.

Thank you chase & khj for your suggestions. I will be careful next time to use cold water and watch out for those things you mentioned!