Raw Copper

Most of the pieces that I scanned here are about 1 to 1.5 inches all the way around, for their irregularness. One piece is about 1 x 1.5 x 1/4 thick, I am wondering if I can drill a hole in it, however if did so and stitched it to my quilt piece it WILL change the color of the fabric. Copper is a mordant/modifier and definately causes natural dyes to experience color shifts. This could be cool, or it could have horrendous effects for which there is no cure.