History:
This site contains the remnants of three different townsites plus the remains of extensive placer mining operations for gold. The first name for a town here was Gila City, established in 1858 when Jacob Snively found rich placer gold deposits at the north end of the Gila Mountains. If fact, the Gila Mountains were first named the Gila City Mountains. In a short time, some one thousand men were working the area but the only permanent buildings were four or five adobe buildings the rest being either tents or crude wooden shacks. The entire town was nearly destroyed in 1862 by a large flood. All that was left by 1872 was a house, stable, and a corral.
The next name appeared when the railroad built a line through the southern part of the state and established a siding near the old Gila City. This new siding was given the name of Dome and was located approximately 1½ miles east of Gila City. The siding was called Dome because there had been an important shipping point on the Colorado River named Castle Dome that had ceased operations with the coming of the railroad. In 1890, Dome was able to establish a post office.
In 1888, a post office was opened near the original site of old Gila City. It was named Monitor after a rich placer deposit located in Monitor gulch and was located at the mouth of the gulch. The postmaster and another man were murdered here in October of 1893. The post office received letters only occasionally but managed to remain open into the early 1900's.
Geology and Mines:
In 1859, a man working in the area could recover over 1 ounce of gold with a few shovels of dirt and several ounces could be recovered in a day. The richest area was in Monitor Gulch but gold has been found up to 3 miles west of Dome. In 1926, a nugget weighing 4.6 ounces was recovered in the area.
There are two types of deposits in the area. One is "pediment" gravels located on the benches that are higher than the surrounding gulches. These gravels contain free gold throughout the bench but higher concentrations can be found at or near the bedrock. Bedrock is made up of cemented sandstones, siltstones, and conglomerates of the Tertiary period. The second type of deposit is found in the gulches themselves and these have provided the richest finds so far.
The deposits have been worked mostly by dry washing although hydraulic mining has been tried but proved unsuccessful. The source of the gold is believed to be stringers and pockets located in the north end of the Gila Mountains. There are some small copper-gold lode mines found in the mountains here.
The placers here are said to have produced 26,000 ounces of gold prior to 1900 and another 500 known ounces since then. If planning on trying your luck in this area, check with the local BLM office in Yuma for current status. The area is extremely hot in the summer months and should be avoided during this time.
References: Arizona Place Names by Byrd H. Granger and California Mining Journal, July, 1988 Pages 11-13.