Abalone (?) shell 5 strand adjustable length necklace

Purchased in high-end seaside Northern Cali boutique (Monterey). I am guessing it’s authentic abalone based on weight and color, but no markings/stamps on necklace at all-likely made by local artisan. Wore a few times but ready to pass along 🪸🐚! Perfect with sundress, straw hat and sandals.