Page 121 - The Geology and Ore Deposits of Sierra County, New Mexico - Bulletin 10

120 GEOLOGY AND ORE DEPOSITS OF SIERRA CO., N. M.
driven from a short winze just below the tunnel level. A second shaft on the contact attains a depth of 175 feet.
DICTATOR AND COVINGTON GROUPS
These groups, consisting of three claims in the Dictator group and four claims in the Covington group, adjoin one an- other and are situated along the north contact of the limestone and the mass of monzonite porphyry that is known as Cuchillo Peak, as shown on the map, figure 8.
The possibilities of these claims were known to the old pros- pectors in the region as early as 1880, and shipments were made to the small smelters erected near Chloride and Fairview, but operations did not continue for long, because the complex ores were not easily treated. Further work was done in 1900 by vari- ous lessees, who sunk several short shafts along the contact. Among these was Thomas Scales of Fairview, who by means of a shaft 130 feet deep and a connecting tunnel 400 feet long driven on the Dictator claim, exposed a good tonnage of ore. Since 1920 T. C. Parker has had control of these groups, either in his own name or in that of the Cuchillo Mines Co., and has done develop- ment work which, though meager in amount, has been well ad- vised and which has exposed an ore zone over 6,000 feet long, fol- lowing the monzonite and limestone contact. Some of the ore from this development, together with ore derived from stoping in the Dictator ground was shipped as a carefully hand-sorted product to lead and zinc treatment plants, or was concentrated in a small and not especially efficient mill into a high-grade lead- zinc-copper concentrate. In all, probably 300 to 400 tons of ore has been mined from the Dictator-Covington group since 1910.
The workings on the Dictdtor group consist of a shaft 130 feet deep, which is connected by a 100-foot crosscut to an adit tunnel 400 feet long as shown on the map, figure 9. The adit tunnel was driven in a southerly direction for a distance of 320 feet through Magdalena limestone, where it broke into monzonite porphyry at what is considered to be the main contact. Small bunches of ore were encountered in short crosscuts driven along the contact at this place. The main tunnel was continued through 60 feet of only slightly mineralized porphyry and then through a wedge-shaped block of hard blue limestone for a distance of 15 feet. At the farther contact of this block of limestone with the porphyry, the tunnel encountered highly mineralized ground, and considerable stoping was done west of the line of the tunnel, as shown on the map. The crosscut to the east, which connected with the old shaft, exposed within the limestone block some min- eralized ground of sufficiently good grade to justify a small amount of stoping. At the extreme end of the tunnel a short winze was sunk and some ore was mined. This are apparently was not all extracted, as the ore shoot seems to continue toward the southeast. In some places on the tunnel level the stopes are