Vintage Navajo Sterling Silver Turquoise Ring 925 sz 6.5 Cripple Creek? Royston?

Beautiful vintage Navajo Native American sterling silver ring featuring a gorgeous turquoise cabochon, with an oxidized rope pattern surrounding it. I have tried to identify where this gorgeous stone is from, and my best guesses are either Royston or Cripple Creek mine turquoise. Purchased this over 30 years ago on a Southwestern U.S. trip. It’s been worn very rarely over the years, and is in nice condition. Ring face is approx 15mm x 20mm. Size 6.5. Fast shipping from a smoke free and pet free home.