Skeleton Man: Tony Hillerman

This was a really good book! A woman, Joanna Craig, is given some hope that her father's remains will be found after the airplane crash in the Grand Canyon in 1956. Her parents weren't married yet, but her father was working for a jeweler and along with a suitcase of jewels (handcuffed to his wrist) he had a diamond for their engagement ring. After the crash, Joanna's wealthy paternal side disclaims the idea that Joanna is their rightful heir and without any DNA proving otherwise, leaves their fortune to an organization. Joanna hears about a boy who gets arrested fro trying to pawn an expensive diamond and the story is that a man living in a cave traded him his shovel for it. He evidently had a collection of diamonds. With the help of the local community a Navajo woman speaks to another native of the area and finds the cave with the mystery man "the skeleton man" deceased. A bounty hunter grabs the diamond and Joanna finds her father's arm, still attached to the case. A storm comes up suddenly and the bounty hunter drowns and the diamonds are lost. Joanna's DNA matches that of the arm and she gets her inheritance.