New Mexico Mineral Symposium — Abstracts

The Picuris Range in north-central New Mexico is an isolated mountain range of Precambrian rocks running 16 mi long east and west from the Sangre de Cristo Mountains to the Rio Grande rift; it averages 10 mi wide. The range consists of great masses of quartzite, mica schist, amphibolite, granite, and occasional pegmatites. The total relief in the range is about 4,500 ft, consisting of a maze of high steep ridges and deep canyons. The highest summit is Picuris Peak 10,700 ft above sea level.

There are two major formations: the upper, Vadito Formation with a composite thickness of 4,500 ft subdivided into a schist member and a conglomerate member; and the lower, Ortega formation of 6,650 ft with three members, Pilar Phyllite, Rinconada Schist, and lower quartzite.

The Picuris mining district includes the entire Picuris Range. Many of the minerals are found in quartz veins. Copper Hill, located 4.0 mi west of Peñasco, contains pyrite, gold, silver, chalcocite, cuprite, malachite, chrysocolla, and limonite; argentite and tetrahedrite have been reported.

On Copper Mountain at the Tungsten mine, quartz veins contain brown tourmaline, tabular crystals of wolframite, malachite, and chrysocolla. This is located 1.5 mi north of Copper Hill.

Near the head of Hondo Canyon (south of Taos) are prospects with quartz veins containing silver-bearing galena. These are 4.0 mi east from US-64. Spongy masses of limonite occur along the veins at the surface.

The Harding pegmatite mine located 7.0 mi east of Dixon is the best-known mine in the district. The major crystallization occurred some 7 miles deep and dates 1330 m.y. B.P. The important, extensively mined minerals include lepidolite, spodumene, microlite, and beryl. More than 50 minerals have been recorded from the quarry. Permits to collect can be obtained from the University of New Mexico Geology Department or from Mr. Griego in Dixon.

At present the major mining is for sericite mica with extensive workings about 2.0 mi south of the crest of U.S. Hill. The mill is located near Alcalde between Velarde and San Juan. In localities around the crest are deposits of sericite-mica clay exploited by the Taos, Picuris, and Apache Indians who make pottery with a distinctly metallic appearance that is a very popular tourist item. A good deal of money is made with this craft. This cookware was made extensively in the late colonial period and was used by the Spanish and Indians alike.

For further information, two publications are:
Montgomery, A., 1953, Pre-Cambrian geology of the Picuris Range, north-central New Mexico: New Mexico Bureau of Mines and Mineral Resources, Bulletin 30, 89 pp. (out of print but available to donwload at http://geoinfo.nmt.edu/publications/bulletins/30/)

Schilling, J. H., 1960, Mineral resources of Taos County, New Mexico: New Mexico Bureau of Mines and Mineral Resources, Bulletin 71, 124 pp. (reprinted 1982)
 

References:

1. Schilling, J. H., 1960, Mineral resources of Taos County, New Mexico: New Mexico Bureau of Mines and Mineral Resources, Bulletin 71, 124 pp. (reprinted 1982)