Greenlee Co., Arizona, USA

Hello, all!

I picked up some material from the giveaway tables at the recent PMA Symposium in Redlands, California attributed to "near Morenci, Greenlee Co., Arizona". The minerals to look for were libethenite and pseudomalachite. I took the following three images (2-4 mm FOV) that appear to show both minerals, at least visually. Mindat has one location in Greenlee Co. with libethenite:

[www.mindat.org]

And, no locations with pseudomalachite. Also, no photos of either mineral. Is anyone out there familiar with the material? Perhaps someone who also attended or organized the PMA Symposium can chime in and provide more information about the locality, more than "near Morenci".





Thanks!

Steve Stuart

As part of a winter collecting trip and vacation my brother and I drove up through Clifton and Morenci during December 1985. When we arrived in Morenci we discovered that the mine was closed due to a long running labor strike. Since it was late afternoon we decided to stay overnight in Morenci anyway. The next morning we headed north out of town and and within less than a mile had a flat tire. I pulled to a wide spot on the west side of the road and while changing the tire noticed a green rock buried in the road fill. When I finished with the tire I dug this rock up and spent the next hour or so breaking it apart. I brought home two flats of pieces, but did not do anything with them until a couple of months ago.

I expect that this rock in the road fill must have come from one of the many pre-open pit mines in the Morenci area, but have no idea which one. One would need to have a lot better knowledge of the mining and highway building history of the area than I do to even make a guess. That is why the location only reads "Morenci".

Any analysis done on the minerals?

The pale blue material is chrysocolla. EDS analyses show both the green balls and the green needles to be pure copper phosphates with the correct stoichiometry to be pseudomalachite and libethenite. Raman spectroscopy done by Robert Jenkins shows the green needles to be libethenite.

Received an e-mail from Bob Housley indicating that he has Raman spectra for the green spherical material, indicating them to be pseudomalachite:

"Steve,

I finally got a chance to run the Raman spectra of the green balls from Morenci. I ran both the larger dark green, almost black, balls and the smaller apple green balls. They are both pseudomalachite as we thought, so I think you can now confidently post your pictures.

Robert Housley"

I'll post some images to Mindat.

Steve