I lost the place where someone was asking how to get stains out of dresden plate blocks. (remember, I'm new). Recently I went looking for something to clean up my wedding dress jacket which I had just put in tissue, and stored 25 YEARS ago. It is satin ribbon & lace. I found a product called "Sharon's Solutions". I e-mailed a question to the site, and 10 minutes later my phone rang, and this nice owner answered my question, talked at length, she works out of her home. I'm sorry to say I haven't worked with it yet, another WIP, but check the sight out, it may help you.
www.sharonssolutions.com

My solution for vintage fabrics (whites) in old tablecloths or quilt blocks, is to rub a fresh cut lemon in the stain. Squeeze the juice and really rub it in, and then put out in strong sunlight for a couple of hours. You could, if you were worried about nearby colors fading, mask them.

If you have a Hancocks nearby they have a whole line of different stain removers for different stains. Check with them.

Thank you for the suggestions. I'm dealing with a lot of little rust dots all over the muslin, so I am going to need to soak the entire block. I wish it was just a spot or two!!

Old but sure fire solution. Works on any stain I have come across.

my mom did this before, and it does work

I learned it from an old woman who sold vintage clothing and linens in one of the big flea markets in NYC, about 30 years ago, and it has never failed me. I love vintage 50's printed tablecloths and I frequently get a great deal because of stains. But I almost always can get them out!

Lemon juice, good information. Thank-you.

I cannot tell why it's true, but it works way better with fresh lemons than with lemon juice out of a bottle.

Wow, the things I can learn on this board. It always amazes me.