I did two of these pendants.  I made the one on the left first, and when I finished, I realized the wire I was using was mismarked and was actually too big.  This made sense because it was extremely hard to manipulate the wire.  The cabachon is floating above the bottom of the pendant ont his one for some reason, but it is secure.  The second one I made with the 18 gauge wire and this project went much better.  For both pendants, I used aventurine cabochons and copper wire.