Bulletin 67—Mineral deposits of Lincoln County, New Mexico

By G. B. Griswold, 1959, reprinted 1979, 1988, 117 pp, 11 tables, 31 figs., 12 plates, 1 appendix, 1 index.

Lincoln County has yielded a variety of metals and minerals: gold, coal, iron, lead, copper, zinc, fluorite, bastnaesite, gypsum, tungsten. In addition, deposits of molybdenum, thorium, uranium, and manganese are known, although no significant production has been recorded.

The White Oaks district produced almost $3 million in gold from the time of its discovery in 1879 until shortly after the turn of the century. This district was the leading producer for the entire county. The Nogal and Gallinas districts produced significant amounts of metals during the late 1800s and early 1900s. Lesser districts, such as the Oscuro, Jicarilla, and Schelerville, have produced gold, copper, and other metals intermittently in the past. Mining was revived during WW II and later years to produce iron, fluorspar, and bastnaesite in previously known districts, but mining is now practically at a standstill. The total recorded production for Lincoln County to date is estimated at approximately $5.5 million.

Excluding coal, gypsum, and placers, the majority of the deposits are of hydrothermal origin, being intimately associated with the widespread igneous activity evident in Lincoln County. The temperature of depression of the deposits extends from epithermal to pyrometasomatic. The composition of the various igneous intrusives appears to have controlled the type of mineralization found in each district.

The known deposits of the area studied do not appear to favor economic exploration under present market conditions, but several of the iron and fluorite deposits may be exceptions. Future exploration by courageous prospectors may completely reverse this discouraging outlook.

The mineral deposits of Lincoln County were studied as part of a continuing effort by the NM Bureau of Mines and Mineral Resources to provide individual reports of the mineral-producing counties of the state. This bulletin doesn't attempt to appraise to any great degree the commercial potentialities of the various mines and prospects of the county; instead, the known mineral deposits are described briefly for the benefit of prospectors and others concerned with the types and modes of occurrence of ores previously mined, and the occurrence of other mineral commodities of possible value.

The study describes the entire county. The southwestern part of the area, including the Oscuro district, now lies, however, within the White Sands Missile Range of the Department of Defense. Inasmuch as the Range is necessarily closed to the general public, that portion of the county was not examined for this bulletin. The brief description of the Oscuro district contained herein was extracted from the works of earlier investigators.