I wanted to add silk ribbons with beads knotted on them into my friend Vicki's tangerine necklace. They only had yellow silk ribbons at my craft stoore. So I bought to Sharpie permant pens in light and dark orange.
I wadded the ribbons up on a paper towel and dabbed them all over with both colors. They were still more spotted than marbleized. I was doing this at a friend's home (without my camera, of course). She had no isopropyl alcohol, so I sprayed this ribbon generously with perfume, liquifying the inks. I massaged it around, rinsed with water and the pressed the ribbon with a handy nearby curling iron.
Then I added a tiny crimp to one end. It is gold metallic in these pictures. I strung the orange crystals and knotted on both sides of the crystals. Then after all that effort, I hated how it looked with the necklace and did not end up using them at all.
But it was super crafty!