Just south of I-10 on the east side of the San Simon Valley in the Peloncillo mountains lie several faults with old mines and prospects. One of these, the Johnny Bull mine, "produced an unknown amount of copper, mostly before 1905" (1). The site sits below McGee Peak on the west side of the Peloncillo mountains just across the ridge from the Carbonate Hill mine, another mine which produced lead, zinc, and silver. Parking at the turnoff to the mine the group headed up hill.
The area is characterized by Mississippian aged Escabrosa limestone
with an intrusive band of volcanic rock. Along the contact between these 2 groups and near the visible fault lines mineralization occurred and the mines and prospects are found along this interface. Vertically oriented bands of mineralization may be seen at the surface and in the old adits and shafts, see below. In the mine dump outside of one of the adits turquoise may be found. Small pieces, light to medium blue in color, dot the dump that spills down the hillside.
The groups first stop was an old stone 3 room building. Perhaps the mine headquarters, this building shows some interesting architectural details including arched windows and doors. Continuing uphill the group came to 2 adits. Above this were several vertical shafts with a headframe, and 2 ore shoots leading down to the level of the adits. After some exploration, the group scattered with some heading south at the elevation of the headframe while others wandered back down hill before heading south across the exposed limestone slope of the Peloncillo mountains to other adits and prospects. Passing a number of dugouts along the walls of the arroyos, these may have served as simple miners sleeping quarters. Arriving at another major working the group took a break and ate lunch while looking for small chips of turquoise. Similar to the other workings, this site was composed of 2 horizontal adits with a vertical shaft leading to the surface above the adits. A bird, perhaps a raven, had built a large nest on a ledge in the vertical shaft next to an ore vein, see image below. Sheltered from the wind and predators this nest still has a nice view of the greenery but in this case it is exposed copper mineralization.
A short winter hike of only about 3 miles, everyone seemed to enjoy a day out on the landscape. The map for this hike may be found here or on the hiking page.
1. Mining Districts of Hidalgo County, New Mexico
|Old house at the Johnny Bull mine.|
|Headframe at the Johnny Bull mine.|
|The last load, an ore shoot below the headframe.|
|The nest egg. Bird nest next to ore vein.|
|Mineralization in a vertical shaft.|