I wanted to try and re-create this using scrap yarn. I started out looping the yarn around cardboard circles to make the medallions, but then realized they wouldn't have the right heft to weigh down the necklace and make it sit right. So I used my handy-dandy awl (if you don't have an awl, I highly suggest you pick one up at a yard sale or something because you can use it for all kinds of really important tasks, like poking new holes in your leather belts!) and put a hole in a couple giveaway buttons. After threading the yarn through those, I knew that I would have the weight I needed.
I picked colors that complimented each other and centered them around a button looped in bright pink mercerized cotton. I sewed the medallions together and knit two long strings of i-Cord out of the bottom-most medallion color. Next time I'll use a super soft yarn for the strings.
The strings are long enough so that you can vary the length, but I think it's best if it sits right on the chest, like so.
Pretty cool, huh?