New Mexico Mineral Symposium — Abstracts

Most every Arizona collector has encountered gypsum near St. David (roses) or the Camp Verde area (pseudomorphs after glauberite). If you are a bit more adventurous, or just plain crazy, you may have seen white, fur-lined walls in an underground drift composed of epsomite or halotrichite. Maybe you have even gotten lucky and found a recognizable barite crystal. Arizona also has a number of localities for which the conditions and the subsequent sulfates are unique or certainly one of a handful of such localities across the world. There are two distinct and widely varied groups of sulfate minerals gracing the cabinets of collections throughout the world. The first, of course, are those minerals occurring before the influence of man. Minerals like world-class spangolites from Bisbee or linarites from the Mammoth-St. Anthony and Grand Reef mines, a Magma mine barite or leadhillite from Tiger. The other group occurs as the result of the intervention of man. These are the post-mining minerals, some of which are quite astounding in their own right.

Thirteen new sulfate minerals were first described from Arizona, seven of which resulted from the burning of the orebody in the United Verde mine at Jerome. The pyrite and copper sulfides caught fire in 1894 and remained sealed until 1928. During that period numerous attempts were made to quench the fires, including the use of pressurized air, water, carbon dioxide, and steam. It was the multiple surges of water and carbon dioxide that helped provide the environments in which seven new minerals formed, including native selenium, and over a dozen minerals were described. Access to these areas resulted when the United Verde open pit began intersecting cracks, thus allowing hot gases to escape. Three minerals are still unique to the United Verde, and they are guildite, yavapaiite, and lausenite. The other species are butlerite, ransomite, jeromite, and selenium, along with alunogen, copiapite, coquimbite, voltaite, and claudetite.

The Mammoth-St. Anthony mine hosts a significant group of rare and spectacular mineral species. The mine really came into its own as one of Arizona’s premier localities during its last mining period from 1934 to 1953. Mine management recognized the value of its minerals and had one or more of their personnel collecting specimens for the company. There are two periods in which sulfate minerals formed, the first, referred by Dick Bideaux as the normal sequence, produced anglesite and devilline. The second, called the anomalous sequence, resulted in beaverite, brochantite, connellite, linarite and bobmeyerite. There are also sulfate/carbonate species in this second sequence which include leadhillite, susannite, plumbonacrite, caledonite and wherryite.

The mines of Bisbee comprise one of Arizona’s great copper mining districts and is also its premier specimen producing locality. Two new sulfates were first described from Bisbee, chalcoalumite and spangolite, and although the type specimen is labeled Tombstone, it is almost certainly from Bisbee. Additional and noteworthy sulfates include antlerite, anglesite, brochantite, connellite, cyanotrichite, leadhillite, and gypsum. The antlerite and connellite crystals from here are some of the world’s finest. Leadhillite is overshadowed by the Mammoth-St. Anthony mine but is nicely crystallized with distinctive white bladed crystals.

Bisbee’s other group of sulfate minerals are the ones forming in the mines. It is not uncommon to find chalcanthite and halotrichite growing in a number of old mines throughout the state. What is unique to Bisbee is the suite of species occurring there. Dick Graeme and his two sons, Richard and Douglas, are responsible for this information. As they explored the mines, not only did they extract numerous specimens, but they also preserved information about the depositional environments. Post-mining gypsum crystals adorn a number of collections. Miners would find these lining drainage ditches and iron pipes. The other species include melanterite, boothite, ransomite, halotrichite, coquimbite, copiapite, kornellite, voltaite, chalcanthite, hydrobasalumnite, and goslarite. Due to the humid conditions these minerals form in, most remain where they were encountered and phtotographed.
One other notable locality for its sulfate minerals is the Grand Reef mine. Most famous for its large linarite crystals, up to two inches long, it is also the type locality for two sulfates, grandreefite and pseudograndreefite. Caledonite, anglesite and creedite also occur here in crystallized specimens.

A number of other localities throughout the state have produced fine specimens. The barites from the Magma mine at Superior are Arizona’s best and range in color from white to golden to black and in crystals up to two inches across. Other barite localities include the Cerbat Mountains, the Rowley mine with mimetite and wulfenite, the Old Reliable mine, near Mammoth, and from the Puzzler mine in the Castle Dome district. Gypsum crystals up to two inches occur on siderite from the Antler mine, with azurite at the Castle Dome mine near Miami, as crystal groups and with colorful copper inclusions from the Mission mine, and associated with both azurite and dioptase from the Morenci mine.

Cyanotrichite has been produced from the Maid of Sunshine mine, near Courtland, and the Grandview mine in the Grand Canyon. Brochantite in association with azurite is known from the Silver Hill mine, north of Tucson, and the Castle Dome mine near Miami.