It's super simple - I tatted it in DMC Perle 8 with size 10 glass beads and a magnetic clasp. The pendant is one I found at Michael's - it's by Blue Moon.
The basic pattern is R 4-4-4-4, with a little bead at the top of the ring. The chain is 4-4, with a bead in the only picot. Too simple for words. I did use a SCMR to attach the pendant - all done with chains of 4 ds separated by a bead, until it was long enough to attach the pendant. True confessions - I took the ball thread off the shuttle here and threaded it through the hole in the pendant before closing the SCMR. I am not as fine a tatter as Queen Jane, who I'm sure would have come to a better solution.
I'm very pleased with my necklace. It's very light and super cute. I wore it to church this morning, and on the way there I said, "I'm really diggin' my new necklace." Moe said, "It's a good thing it's not diggin' into your neck." Hee.