Here are a couple of excerpts from published works that talk about the mine at Fish Lake:
In 1966, I saw for the first time what was reported to have been a copy of an old Spanish map which had been found near the bodies of several slain Spaniards by Thomas Rhoades in 1856. The original map had been given to Caleb Rhoades prior to the death of Thomas Rhoades and the copy was obtained by the Powell family following the death of Caleb Rhoades in 1905. The copy shown to me in 1966 had been obtained from Sadie Jensen (Sidsie Jensen Rhoades Hartzell's younger sister) in 1940 by Clark Powell, Sr.
The area to be searched, based upon the contours of the map and according to the Powell family, was the Rock Creek - Moon Lake region. This conclusion was reached (by the Powells) for a number of reasons, namely; Caleb himself had drawn a map showing a gold mine, a tree and the date of 1856, and he had placed its location west of Moon Lake; the ~blue lake~ of the Spanish map seemed to match the shape and location of Moon Lake; and the ~brown lakes~ of the same map seemed to match those shapes and locations of the Brown Duck Lakes. Therefore, the Powells had concluded, the major drainages shown on the old Spanish map represented those of Rock Creek and the Lake Fork River. And certainly, they seemed to have a good argument, especially since the copy of the old Spanish map also showed a mine and a tree in approximately the same location or area shown by that of Caleb's own map.
But there were too many inconsistencies. The original Spanish map (found by Thomas Rhoades in 1857) had contained various words and instructions in Spanish to supplement the map, and the copy in the possession of Mr. Powell had no such writing upon it. Furthermore, if the mines were indeed located somewhere in the Rock Creek - Moon Lake region, then why did Thomas and Caleb Rhoades travel up the Weber River, the upper Provo River and the North Fork of the Provo River during their initial search for the mines? And another point of argument, as far as I was concerned, was that of the old Spanish trail as shown on the old Spanish map. Supposing that the trail did run along the banks of the Lake Fork River, as Powell had suggested, why then did they (the Spaniards) cross the river to the east and then cross it again to the west just south of Moon Lake? I knew that area well and there would have been no reason nor purpose for them to do so.
It was my firm belief that the ~blue lake~ of the old Spanish map was probably indeed a lake, but that which appeared to be ~brown lakes~ were probably peaks or mountain ridges and not lakes at all. I felt I was correct in my hypothesis that the map did not belong to the area of Rock Creek and Moon Lake, but, at the same time, I did not know where it had been intended to be used.
Later, after having obtained accurate copies of the old Antonio de Reinaldo Spanish maps from the personal possessions of Olive Rhoades Westenskow (daughter of John J. Rhoades) I finally learned the true location of the mines, for the Spanish inscriptions of the map indicated that they were near the headwaters of ~the Timpanogoes~ River (Provo River):" See Map #011
...Several new 7.5 topographs were purchased and major landmarks were pinpointed. An over-lay was made of the Spanish map, using the distance scale as given by the Spaniards, and the contours and landmarks of both maps coincided almost perfectly. But most astonishing, perhaps, was the fact that the northernmost mine shown on the old Spanish map rested, according to the 7.5 topo map, near the shore line of a lake presently known as ~Fish Lake." Fish Lake Basin was just over the mountain ridge to the north from the old Rhoades cabin at Scout Lake which had been discovered by that ill-fated expedition of 1920. The old trail, which was described by A. A. Davidson as leaving the cabin and running up ~the steep and rocky mountain," led north over the ridge toward Fish Lake Basin.
Upon working the Spanish over-lay upon the 7.5 topograph I also found that I had been right in my argument with the Powell family as far back as 1966 and 1967. The ~brown lakes~ of the old Spanish map were indeed plateaus, peaks and basins, not lakes at all, and at least one of the so-called drainages proved to be nothing more that a baseline of a ridge from one prominent peak to another. The trail ~crossing the river to the east and crossing back again to the west~ had been done for a purpose, the crossing of the Upper Provo River Falls. The ~blue lake~ was a lake, but it was Trial Lake and not Moon Lake.
The following narration, taken from my own diary, gives a brief account of that search and of my discoveries:
~This morning I chartered a plane at Salt Lake City and flew over the headwaters of the Provo and Weber rivers for the purpose of obtaining aerial photos of the major landmarks shown on the old Spanish maps. During the flight I did sight several portions of the old trail, particularly in those areas of steep descent where it dropped off the mountain into the basins, but I could see nothing else from the air other than basic landmarks shown on the map. It was amazing how the map compares to the actual lakes, peaks and ridges...
~I've developed and studied the color slides taken from the plane (over the Mirror Lake area) and have discovered what appears to be an old mine or mine dump at the northwest edge of Fish Lake...
~Locating the old Spanish Trail from the top of the ridge to the bottom of the basin was not difficult - the sides are steep and the trail was cut deep, but locating it anywhere along the top of the ridge has been difficult....At the bottom of the ridge, near the northwest corner of Fish Lake, there are the remains of an old, collapsed tunnel, as seen in my aerial photo. The timber exposed at the face of the mine is very old and very rotten. Approximately 30 feet of this tunnel has collapsed. It appears as though someone in the past has attempted to reopen the old mine, but with no apparent success, but some attempt had been made. This mine's location corresponds precisely to that shown on the old Spanish map -- and there are several Spanish symbols carved here in the pines near its entrance. There seems little doubt but what it is the Pine Mine #3 (Caleb called it the Rhoades Mine in 1859). There appears to be no dump site and that is also a good earmark for being that of old Spanish workings, or if there was a dump much has been covered (or washed away) by the waters of Fish Lake since its enlargement due the old dam....being rebuilt.
~Spanish symbols along the old trail have led me to two very old cabins which are located approx. 2 blocks from the old mine tunnel -- these symbols also lead from the cabins to the mine. The trail is wide through the timber and large mountain rock, many large rocks totally removed from the trail and placed to one side or the other of the trail, and a portion of the trail is submerged by the high water of Fish Lake. ....One cabin is almost completely rotted away - it is very old, probably Spanish. The other cabin is made of large logs, untrimmed at their ends, and has been at one time set afire; it is charred badly and the top portion of the walls and the roof have collapsed....This larger cabin, which is only about 60 feet from the older cabin, appears to have been built -- probably around 1870 or 1880 as near as can be determined. Relics found at the cabin sites were an old brace and bit (late 1800's), a three legged iron forge, minus bellows, various old and rusted buckets and tin cans, and an old horse-drawn scraper as used for grading or scraping rocks and earth (this item does not appear that old -- may have been left behind by the dam building crew)....A dam is located on the northeast end of Fish Lake and it has a handwheel to adjust the headgate -probably built during the 1930's as were the rest of those government projects.
This mine [...] is shown on the second Spanish map as the MINE OF (the) SANTA ANNA or the mine of the Weber River if we use present-day names of the drainages. (See Map #009.)--Lost Gold of the Uintah.
Fish Lake is situated at the head of the Dry Fork, with an old mine located only a few yards from its shoreline. Thomas Rhoads called several of the mines shown on his maps, the Pine Mines. He drew a pine tree on one of those maps to identify them. (See Map H). Upon returning from one of his frequent prospecting trips into that area at the headwaters of the Weber River, Caleb Rhoads was heard to boast that he had located one of those Pine Mines, something his father had been unable to do. The late Gale Rhoades believed that mine on the shore of Fish lake was one of the Pine Mines, and recorded his claim to it at the county seat at Coalville, as Pine Mine #3, on July 25, 1978. Since his death, new locators have called that mine the Santa Ana. The Pine Mines which Thomas Rhoads searched for, one or more of which he may have discovered at the headwaters of the Weber and Provo rivers, should not be confused with another group of Pine Mines located by Caleb Rhoads in the Rock Creek and Brown Duck Creek country of Duchesne County, which mines will later be described at length. The Pine Mine #3 located on the shore of Fish Lake on the Dry Fork of the Weber River, called the Santa Ana by some, requires some clarification.
The person calling it the Santa Ana did so thinking it was the mine shown on the 1851 Reinaldo Map; but in fact the real Santa Ana Mine is located near Rhoads Lake on the Gardners Fork of the Weber, several miles to the south. Wayne Handy discovered the real Santa Ana Mine on Gardners Fork nearly forty years ago. The upper Weber River is a glaciated wilderness of rock slides and rugged rocky mountains. Some prospectors have become discouraged and question whether there could be any valuable ore deposits in that glacial moraine and limestone structure. The Utah Geological Society's yearbook for 1969 answers that question with the following: ~The Park City Formation, a strong ore-bearing structure, is exposed from Fransom Canyon, at the northeast corner of Rhoads Valley, and along the upper course of the Weber River to Moffat Pass, where it disappears under glacial deposits." Almost anywhere the Park City Formation breaks the surface, ore-bearing veins or fissures can be found. Not all are worth mining, but even low-grade veins could lead to valuable ore bodies at depth.
The author first investigated that old mine at Fish Lake during the early 1950s, before its portal had caved in. That tunnel was driven into red shale, and judging from the size of the waste dump, it was probably less than one-hundred feet in length. The waste dump extends into the lake, so much of it has been eroded away over the years. Some who have only seen that mine during recent years claim that several old log cabins close by were built by Caleb Rhoads, but they weren't; they were erected by pioneer stockmen who constructed a small dike at the lake's outlet. A few years back a person who should best remain nameless carved the initials ~C B R~ on severla large pines near those cabins, but to anyone familiar with old tree carvings, it is obvious that htose initials have been recently cut. Just how old that mine by the lake might be is difficult to judge, but it is in an area rich with old Spanish mines. --Faded Footprints pg 52 & 53--Greg (http://www.uintahtreasure.bravehost.com