Vintage Coper and Sterling Turquoise Necklace Genuine not a Fake

In good condition with no chips or cracks in the stone. I have had this for years. I bought it in Albuquerque about 25 years ago and I think it was older back then. The chain is coper and the bail is as well. Sterling silver ball accent on the bottom of the pendent. It does show wear to the back of the pendent see pics please. 16 inch chain