New York Mine

Mine Description

The New York mine is situated in upper Ontario Canyon on the northeast slope of Bald Mountain,l mile south-southeast of the Ontario No.3 shaft, two-fifths of a mile south of United States land monument No.1, and immediately south and west of the Naildriver ground. The shaft is situated about 300 feet east of the main creek bed in the canyon.

It comprises half a dozen patented claims, which in early times had been only slightly opened. Thus in December, 1888, a lower and an upper tunnel had reached only 80 and 70 feet, respectively. During the great activity of 1903-4, when many companies were organized to mine in Park City, this ground was taken by the New York Bonanza Co. Local residents took the larger part of the stock and the development was placed under the direction of experienced mining men of the district. Sinking and drifting at successive levels were pressed with vigor and good ore was discovered. Development has been regularly continued and some shipments of excellent ore have been made.

The ground is opened through a double-compartment shaft and levels have been turned at depths of 200, 300, and 400 feet. From the 400-foot level winzes have been sunk and levels have been driven at 500 and 600 feet. Since the writer's last visit, it is understood, a 700-foot level has been driven. The 200-foot level extends northeasterly somewhat over 100 feet; the 300-foot northeasterly, southwesterly, and southeasterly a little over 100 feet in each direction; the 400-foot level southeasterly about 900 feet, northerly 300 feet, and northeasterly about 700 feet; and levels from the winze extend northeast and southwest for a total of several hundred feet.

The property lies geologically in an area of Weber quartzite, which has. been fractured in northeast-southwest, northwest-southeast, and north-south directions and intruded to a small extent by diorite porphyry. The prevailing dip of the sediments is 20°-30° NW. Underground workings, unlike the surface exposures, reveal considerable calcareous sediment.

Traversing this general country rock in a northeasterly direction about 135 feet north of the shaft are croppings of quartzite breccia stained with limonite. This material has been traced for some distance on the surface and is cut by the shaft about 250 feet down. It was this mineralized breccia zone that determined the location and development of the property. The workings cut some quartzite and some silicified limestone, but contrary to what would be expected from surface indications they are mainly in metamorphic limestone. Thus the 400-foot station and the north drift are entirely in marble; the northeast drift is in marble; and the southwest and southerly drifts are in marble until near their faces they enter quartzite. The dip near the 400-foot station is 35° NW.

The three systems of fractures did not disclose intersections which conclusively proved their relative age. The most important system was clearly that trending northeast and southwest. It was evident in one place that the intrusive is earlier than a northeast fissure.

The principal occurrence of ore noted was along a northeast fissure zone which dips southeastward. From the point where it was cut on the 400-foot level, about 50 feet south of the shaft, it has been opened laterally for several hundred feet. At the northeast it has been opened vertically above and below this level and at a point about south of the shaft has been followed down for about 300 feet. Good ore occurs in this zone through a width of 3 to 4 feet in seams or bands 6 to 20 inches wide and in winzes. Both walls were limestone 100 feet below the 400-foot level at the winze, also at the 600-foot level, where the limestone is fresh and blue or black. The trend holds fairly constant, being on the 500-foot level N. 65°-75° E. and on the 600-foot N. 55°-60° E., with the downthrow on the southeast.

The ore left in the walls of the stope on the 400-foot level showed galena and pyrite with considerable carbonate. Eight inches of solid sulphide ore with carbonate outside occurred 170 feet below, and on the 600-foot level an 8-inch vein showed galena, gray copper, and azurite. Ore of this character in a somewhat stronger vein is reported to have persisted downward as far as opened, at least for 760 feet.

The ore shipped has yielded lead, silver, copper, and gold. Apparently the earlier shipments gave more copper, and those from the 760-foot level gave gold. Thus the shipment from that depth made late in 1906 showed 109 to 131 ounces of silver to the ton, 12 to 20 per cent of lead, and $1 a ton in gold.

Source: Geology and Ore Deposits of the Park City District, Utah, 1912 - USGS

New York Mine MRDS details