Beautiful Substantial Necklace Black Stones, Grays and Beige Shell, 36" long NWT

Beautiful and Substaintial necklace, I do not have the original details, but the stone appears real either agate or onyx possibly? (weighty) as well as large shell beads. Weighs about 4 ounces. Measures approximately 36" in length with a lobster clasp and extender chain. Easy to put on over the head without using the clasp in most cases. Ships out quickly after successful payment in completed Thanks!