I added some to a log cabin a loooong time ago. They did not have rosettes, though. The gilded printing mainly came off in the wash. I just opened them up, took off the paper label, and worked with them as fabric. I put small circles appliqued over the holes that the string had gone through.
Look at them closely before you do anything - if the rosette was glued in place to the backing, you may have to be creative. Also, check that deep colors like purple are colorfast. I don't remember using stabilizer, but it wouldn't hurt. I would definately suggest a wall hanging would be more suitable than a bed quilt. Maybe a French braid (using the rosette color as the square part (or satin if you do not have enough plain ribbon parts.) around a center medallion of the rosetted ones. Do you have pictures?