May Program Report: New Mexico Micros, presented by Dr. Scott Braley

Synopsis by Andy Thompson, MSDC Secretary 

“Tonight, I am going to talk to you about six (mining) localities” in New Mexico, Dr. Scott Braley said, some well-known and others less so. All of them have been long abandoned with their ores having been played out. But for micromineral collectors like Scott, each of the sites is a rich resource for finding beautiful and intriguing specimens.

To make sure there would be abundant time for him to share his many photos of the minerals, he said he would deliberately keep his presentation and explanations on the light side, without going into a lot of details about the geology of each mining region.

Readers: The purpose of this report is to give you a few snapshots of Scott’s presentation and encourage you to go to the YouTube video of his talk so you can enjoy it in its entirety (length: 40 minutes with Q & A about 35).

Simply put, the geological context of these mining sites is they are spread out along two mountains that he said are “kind of linear. This whole thing is just one big fault that kind of thrust up.”  Below is the list of those sites, along with a map showing the location of each identified by a numbered star.

1)      The Hansonburg District

The first locality, Hansonburg, is roughly 35 miles east of Socorro, NM and includes well over a dozen mining sites. The District is famous for its fluorite and secondary copper minerals, including linarite, for which this area is the type locality as it is also for several other minerals.

A number of the fluorite crystals, CaF2, have considerable structural complexity. For the specimen below, from the Sunshine Mine #2, Scott pointed out its complexity increased as the crystals grew and added a second generation of crystals with new shapes and colors, octahedrons, over other octahedrons, and also over chalcopyrite.

Besides fluorite specimens, Scott showed some gorgeous copper secondary minerals from other mines in the Hansonburg District

Some of the specimens Scott has collected came with mysterious identities yet to be discovered. Below, for example, is a sulfur specimen which often has anglesite and cerussite inclusions. But, he asked, what is the super tiny, beaded, hair-like filament atop the sulfur specimen from the Mex-Tex mine?

2)      The Red Cloud Copper Mine

Just a bit east of the Hansonburg mines is the second of Scott’s locations, the Red Cloud mine which he spoke to us about in his presentation in January 2021. He returned there several times for additional collecting and below are examples of a few of his more recent finds. “Vanadinite is the prize mineral up there” at the Red Cloud mine.

One of the pleasures of collecting micro specimens is using photography to explore their hidden mysteries which sometime become apparent only after multiple examinations. The vanadinite specimen shown below, shaped in the form of a cross, is a case in point and is particularly interesting. The large cluster of crystals in the center is mottramite. But contrary to Scott's initial understanding (in 2024), almost all of the small crystals turned out to be plattnerite.

Another example of that thrill of the hunt was evident when Scott showed the hemimorphite (Zn₄(Si₂O₇)(OH)₂·H₂O) crystals below. They generated a lot of discussion among Scott’s audience who were puzzled and intrigued by the “Christmas tree-like” fracture patterns evident below, but whose identity was not evident. [Check out the discussion in the the YouTube video].

3)      Paramount Canyon

Moving to the southwest, Paramount Canyon is the third site whose minerals Scott described for his audience. “It is one of the two known areas in the world where you can find red beryl.”

While exploring this Oligocene rhyolite region including the Taylor Creek Tin District, Scott learned that some of the collected minerals had been formed by vapor-deposition and were extremely hard. That was another insight that captured the interest of his audience.

Below are photos of the New Mexico red beryl crystals which are small and different from the generally red beryl specimens found in Wah Wah Mountains of southern Utah. The smaller NM specimen photos below have a field of view (FOV) of 2 to 3 millimeters.

Historically this area was mined for tin and today, the microminerals found there include multiple forms of cassiterite, as shown below.

4)      Chili West

The fourth location in Scott’s presentation is in the northern part of New Mexico. He and his team of collectors gave it this name because it is literally to the west of a small village, Chili, whose population is less than 100 residents.

Earlier explorations in the 1980s found a road cut that yielded interesting zeolites. So, Scott’s team expanded their search to additional mesas and roadcuts that had surfaced from the ancient Lobato basalt formations. One of them, pictured below, did have zeolites similar to those found in the 1980s and so their extensive search was rewarded.

Toward the top of the steep incline shown above, they found a wall containing numerous vugs whose weathered calcite was of limited interest to the collectors. But just above and below that vug area, Scott found abundant zeolites named in the slide below.

One of the most beautiful examples included levyne, below, which had an overgrowth of erionite.

They also found an abundance of thomsonite which had three forms shown below: square crystals (on the left), blue balls (on the right) and a radiating “scary tentacle version” (at the top center).

5)      Merritt, Socorro

“Historically, the Peak Mining District was primarily for silver mines, and they played out fairly quickly over five or ten years.” More recently, the area had been used for testing explosives, so the old mines have not been open to the public. Nonetheless, the area is known to have a mix of brilliant, colorful microminerals including those below.

The area also has very tiny hexagonal jarosite and probably hematite.

6)      North Magdalena District (Sophia)

This Magdalena District is located near the famous Kelly copper mine and has a large number of small mines and prospects that were never particularly productive. Although mining was limited at the site, the minerals being mined shifted over time and included only a few ounces of silver produced in the 1880s, modest amounts of copper in the 1920s, barite in the 1980s, and silver again in the 1970s.

Miners had reasoned that with the productive Kelly mine nearby, the copper formation may well have run beneath the Magdalena district.  But actual mining efforts found no evidence of that.

The Sophia Mine produced a tiny bit of silver ore and collectors of micros have found specimens of fluorapatite, as shown below. Now a refrigerator blocks the entrance to that mine.

Collectors have also found specimens of white hexagonal fluorapatite crystals shown below. The botryoidal material is either goethite or hematite.

In a second shallow dig site named the Bullfrog #2 “mine,” which Scott described as a shallow hole in the ground, collectors have found micro willemite and hematite specimens, shown below.

Scott said the most interesting mineral to come out of this tiny site is the bright green fornacite shown in the upper left of the three photos below.

7)      Nacimiento, Bonus Site for the Evening

Having covered his six mineral sites with a few minutes remaining, Scott introduced an intriguing story of the successful search for the extension of a copper mine that was submerged and re-emerged a few miles away. Nacimiento is the site of beautiful copper microminerals. That is a story Scott is currently working on and will be the subject of a future talk.

Interested readers can learn about this seventh site and some of its minerals, shown below, by viewing the full YouTube video.

That concluded Scott’s extraordinary presentation and MSDC’s Program Chair Kenny Reynolds thanked him and opened the floor for questions from the Zoom audience.  His answers were as interesting as his presentation and are well worth listening to (presentation of about 40 minutes and an additional 30 minutes of Q & A). The link to the video can be found HERE.

Scott’s audience applauded his excellent presentation. Dan Teich, MSDC’s President and Kenny Reynolds, MSDC’s Program Chair, thanked him for giving such a wonderful program on the microminerals of New Mexico. Dan also thanked everyone for joining our event and encouraged everyone to come to our June 4 meeting where our presenter will be Dr. Gabriela Farfan who will be speaking about the new display of the Winston colored diamonds and other recent highlights at the Smithsonian’s National Museum of Natural History.