"Yuma's Gold" is one of the classic yarns, although not as well known as some of the others.
John D. Mitchell included it in his first book:
[1933 - Published by Milton Rose]
The best account is probably Prof. Dobie's in the essential Coronado's Children (1930). That chapter was reprinted in Long John Latham's Famous Lost Mines of the Old West (1971), but to read it there you'll miss the rest of CC and that would be a shame.
F.L. Coffman and Thomas Penfield recounted this story, but added nothing reliable - the emphasis is on "re." The same may accurately be written about W. C. Jameson's version(s) - give 'em all a miss.
The Dean of Desert Writers, Harold O. Weight, contributed "Yuma Gold" to the August, 1975 [Vol. 36, No. 8], issue of Desert Magazine. If Mr. Weight wrote it, it is certainly worth reading! There are at least two other Desert articles that retell the tale, but Mr. Weight's piece remains the best.
2.0 - Probert cites an Arizona Gazette (Phoenix) article (Feb. 22, 1897) as a source. I have not been able to locate a copy - but I'm looking.