MINES 



139 



VICTORIA AREA 

 Location and extent of workings 



The Victoria area of the New Almaden mine lies 

 north of the central stope area. (See fig. 92.) It is 

 explored by a group of levels that lie between the 

 Santa Rita, Victoria, and St. George shafts and ex- 

 tend from an altitude of about 1,200 feet (600 level) 

 down to about 900 feet (900 level). Also included in 

 the area are the Victoria, Ossuna, Santa Anna, Ore- 

 gon, New Santa Rita West, Ponce, Giant Powder, and 

 Santa Rita West slopes. (See fig. 81 and pi. 4.) This 

 part of the mine was developed chiefly as a northward 

 extension of the workings of the central stope area, 

 and it was first mined through drifts on the 600 and 

 700 levels and from the Day tunnel on the 800 level. 

 Later the workings of the Victoria area became ac- 

 cessible through crosscuts on the 800 and 900 levels 

 from the Randol shaft, and still later they could most 

 easily be reached through the Victoria shaft. This 

 shaft was open when this study was being made, but 

 the manway had been destroyed by caving. The only 

 parts of the Victoria area that were reached were the 

 700-level Relief drift (pi. 5) from the central stope 

 area and the connected Giant Powder and Ponce 

 stopes, but a miner who went down the unsafe shaft 

 in 1947 reported that most of the workings were in 

 silica-carbonate rock and still open. The total extent 

 of the levels in the area is a little more than 1 mile, 

 but almost as extensive are the various nearly level 

 pathways that serve as levels through the old stopes. 

 (See pi. 4.) 



History and production 



The largest ore bodies developed by the Victoria 

 workings were discovered and mined between 1871 and 

 1874, and they probably supplied the ore for most of 

 the 57,268 flasks yielded during that period by the 

 New Almaden mine. In 1874, when the ore bodies of 

 the Victoria area were thought to be largely depleted, 

 the South Randol ore bodies were found, and appar- 

 ently the Victoria workings were not kept open for 

 long after this new supply of ore became available. 

 In April 1891, however, when the Randol ore bodies 

 had been largely mined out, the Victoria shaft was 

 sunk to provide access to the old Victoria workings, 

 which could no longer be reached through the cross- 

 cuts from the Randol shaft. This new shaft was 

 rapidly sunk to the 900 level, and connections were 

 run on the 800 and 900 levels to the old Victoria work- 

 ings. This development resulted in the taking out of 

 some old stope fill and some new ore, but in 1895 the 

 shaft was closed down to reduce expenses. Seven 

 years later, when little accessible ore was available 

 elsewhere in the mine, the shaft was reopened, new 



workings were run on the 800, 900, and 1000 levels, 

 and again minable ore was obtained. Also at this 

 time, in order to move the ore more easily from the 

 stopes to the furnace, the 800-level crosscut from the 

 Day tunnel was reopened. In 1906 the area was again 

 considered to have been exhausted and was again aban- 

 doned. Since then at various times lessees have re- 

 paired the shaft and have obtained an unknown 

 amount of ore from the old stopes. Records- of pro- 

 duction for these various periods of intermittent work 

 are fragmentary, but the writers estimate that no less 

 than 60,000 flasks in all has been recovered from the 

 ores of the Victoria area. 



Geology 



The geology of the Victoria area cannot be described 

 in detail, for very few of the workings were open 

 when the mine was mapped by the U.S. Geological 

 Survey and most of them are too old to have been 

 comprehensively described by the company surveyors. 

 Nevertheless, because the geology to the north and 

 south is well known, it is possible to deduce with con- 

 siderable confidence the broad features of the geology 

 of the Victoria area from the distribution of the stopes 

 and other workings. These follow the upper surface 

 of the serpentine sill that contained the Randol ore 

 bodies to the north and the Santa Rita ore body to 

 the south. In the Victoria area the upper surface of 

 the sill is arched into a gentle anticline striking N. 55 

 W. and plunging about 20 NW. (figs. 93, 81; pis. 5,6, 

 and sections A -A' and C-C', pi. 11). Below an alti- 

 tude of about 1,000 feet the northern flank of the anti- 

 cline is sharply flexed to a much steeper dip along a 

 line that trends nearly parallel to its axis. The geo- 

 logic setting, however, is complicated by at least one, 

 and probably two, thin sills above the main contact. 

 Their presence is indicated by the overlapping of 

 stopes and drifts, particularly in the northwestern 

 part of the area (pi. 4), but no evidence is available 

 to indicate where these thin sills diverge from the 

 main sill. Everywhere in the Victoria area the apo- 

 physes and the upper margin of the main sill are ap- 

 parently converted to silica-carbonate rock. Judging 

 by the distribution and height of the stopes, the shell 

 of silica-carbonate rock along the main serpentine 

 body is at least 30 feet in average thickness, and it 

 may be much thicker. 



Ore bodies 



Most of the ore bodies in the Victoria area appear 

 to have lain close beneath the upper surface of the 

 main sill, along the flatter part of the anticlinal arch, 

 though some ore bodies which overlap these were 

 apparently in thin sills overlying the main one. Ex- 



