I recently used a heap of my offcuts of bazzill to make a bucket load of bleached butterflies.
Try it at home , depending on the dye in your card stock it will give you different effects, you see here on the pink card it changed to a cream colour and on the orange it changed to a bright white....watch out for the other colours in upcoming posts.
Have a go at bleaching next time you want a new take on old stamps.
I used a folded chux wipe and placed it in a container, I used just enough bleach for the absorbent cloth to absorb. Don't forget to clean your stamps thoroughly after using bleach on them.