Ross-Simons - 18kt Gold Over Sterling Scrollwork Seashell Pendant Necklace. 18". Nature-inspired elegance: Detailed with scrolls and 18kt yellow gold over sterling silver, this seashell pendant necklace adds a unique flair to any ensemble. Suspends from a popcorn chain with a 2" extender. Lobster clasp, 18kt gold over sterling seashell pendant necklace.