I checked the Arizona Genealogy Birth and Death Certificates, http://genealogy.az.gov/
but he wasn't listed there.
He doesn't appear in Ancestry (except for your family tree) or familysearch.org.
You could contact the Gila County Recorder's Office, 928-425-3231 and see if they have a death record for him. If he was working at a mine way out of town, his death might not have been recorded. Successful Searching!