64 



GEOLOGIC GUIDEBOOK ALONG HIGHWAY 49 



[Bull. 141 



and had an inactive period between 1875 and 1885. From that time until 

 final closing in 1942, the mine was operated continuously and on a major 

 scale. The Kennedy was worked largely through vertical shafts to a 

 vertical depth of 5912 feet, making it the deepest gold mine in the United 

 States. There are approximately 150 miles of underground workings 

 as well as extensive surface equipment which once included the Jackson 

 Gate elevator wheels and the miles of flumes connected with them. A 

 fair cross section of the history of gold mining and milling equipment 

 may be gleaned from past reports of the Kennedy operations. The work- 

 ings are in Mariposa slate and Logtown Ridge metavolcanics. Minerals 

 described from the Kennedy include gold, quartz, pyrite, galena, fluor- 

 apatite, strengite, sphalerite, chalcopyrite, ankerite, and other car- 

 bonates. The total production of the Kennedy mine calculated on the 

 present price of gold is $45,000,000. Recalculated to fit various price 

 changes in gold, the production figure is approximately $34,280,000. The 

 Kennedy has been idle since 1942. 



The Argonaut mine, across Highway 49 to the northwest of the 

 Kennedy, can be located for many miles in all directions by its lofty 

 water tank. It was first worked in 1850 but had only been developed to 

 a depth of 150 feet by 1876. Except for two one-year periods, when 

 operations were suspended because of fires, the Argonaut operated con- 

 tinuously from 1893 to 1942. The veins are largely continuations of those 

 on the Kennedy property and the geology is similar. The mine was 

 worked through inclined shafts to a depth of 6300 feet along the dip or 

 5570 feet vertically. There are eight miles of drifts, crosscuts and tun- 

 nels, four miles of raises, and 50 miles of stope floors. The total pro- 

 duction of the Argonaut to the end of 1943 was $25,179,160. The most 

 recent operators of the Argonaut dissolved their organization in Feb- 

 ruary 1948. The mine has been idle since 1943. 



Martell, situated two miles northwest of Jackson, is the terminus 

 of the Amador Central Railroad. In addition to its railroad facilities, 

 Martell boasts a lumber mill and curing yard. The logs are fed to the mill 

 from an artificial pond. Trucks bring the logs to the pond from timber- 

 lands higher in the mountains. 



The old Oneida mine was situated close to the northeast of the 

 present site of Martell. Only the mine dumps mark the site, the Oneida 

 having been idle since 1913. It was one of the richest of the early-day lode 

 mines, ore averaging as high as $40 a ton in the early 1860 's. The Oneida 

 has a 2280 foot vertical shaft and several shallower inclined shafts. An 

 inclined winze sunk 250 feet from the 2280 foot level gives a total vertical 

 depth to the mine of about 2500 feet. The total production of the Oneida 

 is something in excess of $2,500,000. 



Three very productive mines are located near the junction of High- 

 ways 49 and 108 about a mile north of Martell. These are the South 

 Eureka, Central Eureka, and Old Eureka. Headframes of the latter two 



can be seen from Highway 49. The South Eureka located southeast of the 

 Highway 108 intersection, was discovered at an early date but was not 

 developed until 1891. Much of the development and maintenance of this 

 mine has been integrated with operations in the Central Eureka as has 

 the Old Eureka, since 1924. The South Eureka has been worked to a depth 

 of 4100 feet and has produced gold to the amount of $5,300,000. 



The Central Eureka, located north of the South Eureka across 

 Highway 108, was discovered in 1855 and was called the Summit mine 

 in its early days. It had a small production prior to 1865 but major 

 exploitation took place after 1896. The Central Eureka and Old Eureka 

 are among the few Mother Lode mines which have survived wartime 

 limitations on gold mining and the rising cost of operation. A great deal 

 of credit is due the present management for being able to remain in opera- 

 tion when other large workings such as the Argonaut and Kennedy have 

 been forced to close down. The Central Eureka shaft is 4965 feet deep 

 along an average dip of 70 or about 4650 feet deep vertically. The wall 

 rocks are Mariposa slate and gray wacke and greenstone of the Cosumnes 

 and Logtown Ridge members of the Amador group, all of Jurassic age. 

 Authorities disagree on the early production of the Central and Old 

 Eureka mines, but the best available production figure for the Central 

 Eureka is $17,000,000. 



The Old Eureka mine is located a half mile north of the Central 

 Eureka headframe in the outskirts of Sutter Creek. It is an early day 

 consolidation of the Eureka and Badger claims and had a very high 

 early-day production. The Old Eureka was first opened in 1852. Workings 

 have been developed to an inclined depth of 3500 feet. A wide variation 

 in early-day production figures exists in various published reports on 

 the Old Eureka. The most probable compilation of figures indicates a 

 total production of about $17,400,000 for this mine. 



The town of Sutter Creek was named after John A. Sutter who first 

 visited the region in 1846 and mined there in 1848. Sutter Creek is a 

 rather harmonious blend of older frame and recent stucco buildings 

 nestled among low hills. A continuous row of gold quartz claims located 

 along the Gold Thrust passes through the heart of Sutter Creek. Aside 

 from the aforementioned Eureka group south of Sutter Creek, the most 

 productive mines in this vicinity were the Wildman, Mahoney, and 

 Lincoln now grouped together under the name Lincoln Consolidated. 

 These mines were discovered about 1851 and were worked both separately 

 and together at various times throughout their history. The Lincoln 

 shaft, which was the deepest of the three, was sunk on an average angle 

 of 63 to a depth of 2000 feet, giving a vertical depth of about 1760 feet. 

 Ore bodies of mines between Sutter Creek and Amador City are mainly 

 at the/ fault contact of Mariposa slate and Logtown Ridge meta-andesite. 

 North of the Wildman, the veins were as wide as 45 feet near the surface. 

 Combined production of the Wildman and Mahoney was slightly less than 

 $5,000,000 ; the Lincoln is credited with $2,200,000 in gold. 



