Hi! Great necklaces, and both look gorgeous on you.
My vote goes to the necklace. It makes a great statement. The pendant is nice too, but for me, it's more of the usual "pendant-on-a-chain" theme. The necklace is far more artistic.
On the necklace, the two-tone gold necklace in your photo is certainly nice if you are looking for a "metal" necklace (there is a lot of metal).
If you might be interested in something a bit more unique, I like the chrysoprase and onyx version:
Bouton d'or necklace, 18K yellow gold, chrysoprase, onyx, round diamonds; diamond quality DEF, IF to VVS.
www.vancleefarpels.com
Same necklace, but two different looks, so it's really what you want.
The all-metal version is safe. The chrysoprase/onyx version is wow to me. It would look very chic with your outfit.
On both necklaces, I would ask VCA to shorten a bit. Both seem a bit long on you, especially the necklace.
Just my two cents. Hope this helps in your decision.