I have a plain string of turquoise beads I picked up for a song (less than $5!). It was too plain to be stylish so I put on a stone pendant I had made out of a black rock I had found at the seashore (you could use a tumbled stone) which I had wound round with jeweler's wire. I twisted it around the stone (in this case across the center) and then made a loop which I then twisted off around the base to secure the wires. I actually had made the pendant BEFORE I thought of putting it on the string of turquoise, but it looks great together!