looks like a newfoundland

Assuming the quilt blocks are cotton... Use only the gentlest detergent, like Woolite in lukewarm or cool water in a basin. Divide all into color piles. Wash only the white/lightest at first, by just squishing the suds through, using your hands, patting them instead of wringing, and letting them soak. Rinse, and dry flat and evaluate your results: Press gently, and examine the seams. Then do some slightly darker blocks, only blues; only greens; only pinks, etc. How much color is coming off into the water? Do the darkest ones last. If you are satisfied that your blocks are washable and the seams are worthy, then go ahead and make a quilt. Best of luck to you.

Would this quilt end up being for you or for your friend?

Have you seen the blocks yet? Have you smelled them yet?

Definitely DO NOT wash them by machine.

Even hand washing can be stressful to a block -

On the other hand, I would not want to work on something that would fall apart in my hands.

I have to agree with the "wait till its quilted" crowd. Too risky to do before that. Shrinkage, ravelling, etc.

Do not wash them before you use them. Judging by the age, they will severely fray. Wash after you make into a quilt.

I also vote for waiting til the quilt is finished..

Don't wash them. They are old and they could fall apart. I have several friends who have done this and regretted it. Put them in a quilt and then hand wash it in a tub carefully.

Is the quilt for her or yourself? If it is for herself she could was them first and if there are any mishaps, she can decide what to do after that. I would be inclined to give them a gentle soak and hand wash.

I would wait. I'ld be affraid of any fraying.

The little dog(haha) in my avatar is a Newfoundland, her name is Maggie and she weighs 136 pounds. She is very sweet!