Newton Mine (Newton Copper Mine; Jackson Mine), Sunnybrook, Pardee Mining District, Amador County, California, USAi

Regional Level Types
Newton Mine (Newton Copper Mine; Jackson Mine)	Mine
Sunnybrook	Residential Area
Pardee Mining District	Mining District
Amador County	County
California	State
USA	Country

A former large lode Cu-Au-Ag-Pb-Zn mine located in the SW¼ sec. 28, T6N, R10E, MDM, 0.8 km (0.5 mile) W of Sunnybrook, on the S side of highway 88 and about 3 miles NE of Ione, about 6 miles W of Jackson, on patented (private) land. Discovered in 1863. Owned by the Dufrene estate and J. H. Lester; Utah Construction Co. (timeframes unknown). Operated during the period 1863 to 1946. Mine was idled between 1909 and 1942. MRDS database stated accuracy for this location is 100 meters.

Mineralization is a polymetallic deposit (Mineral occurrence model information: Model code: 184; USGS model code: 28a; Deposit model name: Massive sulfide, kuroko; Mark3 model number: 93), hosted in greenstone & schist. The ore body is lenticular in form, strikes N40W and dips 70NE at a thickness of 2.44 meters, a plunge of 62-65, and a length of 140.21 meters. Its maximum strike length is 460 feet. It has been mined through a length down-dip of about 600 feet. Drilling has proven that the ore extends more than 800 feet down-dip from the surface. It rakes northward with a pitch angle close to 77 degrees and a pitch length of about 900 feet. Controls for ore emplacement included a zone of structual disturbance found where East-dipping foliation lies adjacent to West-dipping foliation. This zone extends through the Newton Mine. Due to the lack of lithologic correlation across the strike, this zone is more suggestive of a fault along the axial plane of an isoclinal fold than a zone of stretching and displacement in an overturned limb of a major anticline.

A thick series of schists and greenstone of low-grade metamorphism occur. Graded bedding was observed on rocks and dips steeply E. Capping higher, neighboring sand, dipping W with no evidence of deformation. This sequence lies unconformably over older rocks. Local rocks include Jurassic marine rocks, unit 1 (Western Sierra Nevada and Western Klamath Mountains).

Local geologic structures include folds having amplitudes and wave lengths ranging from 1 to 10 feet. A system of cross-faults show apparent strike-slip displacements of 20 feet. These faults displace the ore body. Slickensides were observed with a low pitch. There is one post-ore reverse fault on the 200 foot level that dips 55-60W, net slip parallel to the dip.

Workings include underground openings with an overall depth of 167.64 meters. Workings are extensive. During the period 1942 to 1943 the U.S. Bureau of mines put down 5 diamond drill holes totaling 4,258 feet. Hole No. 1 intersected the 400 foot level of the mine; No. 2 encountered ore; Nos. 3 & 5 showed ore at depth; and, No. 4 failed to intersect ore N of the main ore body. Good indications were provided that the bottom of the sulfide lens lies considerably below the 550 foot level of the mine.

Production data are found in: Heyl, George Richard and Eric, J.H. (1948).

Some Zn was produced but production wasn't recorded.

The ore ranges in grade from 1.25% to 21% Cu, a little Zn & Pb, Au & Ag.

Other Databases

Link to USGS MRDS:	10028080

Other Regions, Features and Areas containing this locality

References