The San Domingo Mine was located in City Creek Canyon.
A newspaper article from 1873 stated the mine "Is being
vigorously worked and a new body of ore has been struck in the east incline." Assay reports showed
the vein to be richer than previous finds, but no exact value is noted. The mine in 1873 was owned by three individuals, Houts,
Robinson & Hampton. It was reported that work would continue vigorously. (1) Just how vigorously and how long is not known, but
another mention in the same paper on the 28th of September 1873 said that another rich vein had been found, and it is "One of the most promising claims in the camp."
Though it is known that the San Domingo was located in Cottonwood Gulch(3), the exact
location of this mine is not known. It is possible that the Treasure Box is a re-named San Domingo, but this is not known.
Further research is needed.
What is known for sure is this: the San Domingo was originally located
on July 6, 1873, and hand picked samples of ore from those early finds assayed for as much as $300 per ton.(3)
(1) Salt Lake Daily Herald, Vol. IV - No. 66, August 28, 1873, p.3
(2) Salt Lake Daily Herald, Vol. IV - No. 94, September 28, 1873, p.3
(3) Utah Gazetteer and directory of Logan, Ogden, Provo and Salt Lake Cities for 1884, Robert W. Sloan, herald Printing
& Publishing Co., 1884, p. 74