New Mexico Mineral Symposium — Abstracts

The Sunshine Mining Company began exploratory drilling, drifting, crosscutting, and rising in the vicinity of the Blanchard mine in November 1958. The Sunshine #1 was the first of six exploratory tunnels developed and it trends eastward. The tunnel dimensions are 12 ft by 12 ft by 405 ft long. No ore was marketed during this period.

The tunnel was virtually unknown as a specimen producer until February 1978 when several flats of galena crystals coated with a lustrous, blue druze of linarite first reached the public at the Tucson Gem and Mineral Show. This was followed by an even more stunning find of world-class linarite crystals in late 1979. Many of these marvelous specimens were brought to the Tucson Gem and Mineral Show in February 1980 and were soon purchased (reputedly for many thousands of dollars) by eager collectors.

Following the incredible 1979 linarite discovery, an effort to locate/recover additional linarite crystals was made by individuals under contract from Western General Resources, Inc. (the leaseholder at that time). This operation continued for several months but no large linarite crystals were found. The operation was closed down by OSHA.

The Blanchard mine including the Sunshine #1 tunnel was claimed (located) by mineral collectors in April 1987, and in September of that year an amazing pocket was opened by the claim owners. The pocket was behind a large gypsum mass near the roof of a raise developed in the search for linarite crystals and had to be reached using a ladder. Initial entry into the pocket revealed large blue and purple cubes of fluorite up to 9 cm on an edge and water-clear selenite crystals in spear-shaped and prismatic habits. The largest crystal was 44 cm long. The pocket dimensions were roughly 1-1.5 m wide by 0.8-1 m high by 5 m long. This pocket eventually yielded dozens of superb fluorite, selenite, and galena specimens.

More recently, the new mineral species, scrutinyite («PbO₂), was described by Taggart et al. (1988) based on specimens from the Sunshine #1 tunnel. Scrutinyite is a dimorph of plattnerite that occurs as very small (less than 0.1 mm) reddish-brown micaceous crystals.

The following is a listing of some of the more noteworthy mineralogical events that have recently been recorded for the Sunshine #1 tunnel:

1) First positively identified location for caledonite at the Blanchard mine and largest crystal (7 mm).
2) First in situ occurrence of pyromorphite from the Blanchard mine. Colorless to slightly gray, transparent, hexagonal prisms were found.
3) Largest and brightest crystals of corkite known to occur at the Blanchard mine.
4) The finest occurrence of hydrozincite and the only known location for fluorescent green fluorite (short wave).
5) Only known occurrence of blue hemimorphite at the Blanchard mine.
6) One of only two significant sphalerite occurrences at the Blanchard mine and without doubt the producer of the finest specimens.
7) Largest known selenite crystals from the Blanchard mine.
8) Arguably, the producer of the finest fluorite specimens from the Blanchard mine.
9) Finest specimens of covellite replacing chalcopyrite.
10) Only known location at the Blanchard mine where corkite expitaxially overgrows jarosite.
11) Excellent anglesite crystals up to 6 mm, rarely found elsewhere at the Blanchard mine.

Confirmed Mineral List
Sunshine #1 Tunnel, Blanchard mine, Bingham, NM 

References:

1. Taggart, J. E., Jr., Foord, E. E., Rosenzweig, A., and Hanson, T., 1988, Scrutinyite, natural occurrences of aPbO2 from Bingham, New Mexico, U.S.A., and Mapimi, Mexico; a new mineral: Canadian Mineralo??gist, v. 26, no. 4, p.