Monday, December 5, 2016

November Field Trip Report

by Club Member Anita Williams

We met as usual in the Visitor Center parking lot on a beautiful fall morning.  Promptly at 8:30 am the vehicle caravan departed heading south towards Lordsburg.  We regrouped at the Pilot station on I-10 fueling up with gas ($.30 cheaper than Silver, but that’s no surprise), coffee and/or breakfast.  There was some "de-fueling" too although we were told there is a rest stop right in Hachita that could accommodate folks in need.

We were heading for the abandoned Apache Mine in the Apache Hills south of Hachita.  We accessed the mine area after a four mile drive on a dirt road.  The area had numerous tailing piles and some trenches and a few debris filled shafts.  Of course the group gathered their buckets and hammers and scattered across the area in search of rock/ minerals samples.

The following data was taken from an article by Wofgang Elston, Mining Districts of Hildago County, NM, in NMGS, 17th Field Conference.  The Apache mine started production in the 1880’s.  Between 1880 and 1929 the mine shipped low-grade malachite in calcite to smelters in El Paso and Douglas to be used as flux in the smelting process.   From 1929 on there has been some production and sporatic exploration.  The mineral deposit was formed during the Laramide (late Cretaceous to early Tertiary age: the time of the uplift of the Rocky Mountains) and was associated with an igneous intrusion in the Apache Mountains.  The associated fluids formed what is called a contact metasomatic deposit.  This caused the limestone formation to be altered/replaced by mineralizing solutions.  The alteration produced the massive beds of calcite present at the mine site, and as a consequence, the beautiful calcite rhombhedrons scattered all over the area.  Other minerals found on site include malachite, azurite, chrysocolla and possibly turquoise. 

After collecting at the mine a few vehicles took off to look for quartz crystals farther down the dirt road.  This part of the road was a bit more challenging with a 2 wheel drive and it is not recommended.  We drove through several steep washes over several miles until we were stopped at a wash out.  Fortunately there were nice pieces of quartz and some crystal terminations scattered over the entire area.  So although we did not get to the specific location we were able to collect some nice samples.  In this area, the quartz is weathering out of the limestone so it is scattered on the surface over a large area.

We all loaded up and drove out in mass in case someone had trouble making it over some of the rougher road segments.  Happily we all made it to the pavement without incident.  There was a photo stop at the Hachita rest area prior to heading back to town with our treasures. 

December newsletter

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