Minerals Found at the Sacaton Mine, Casa Grande, Arizona      By Raymond Grant

     The following is a list and description of the minerals found at the Sacaton mine. It is a compilation from the two trips the Foundation has made to the mine and literature supplied by ASARCO.
Antlerite - is reported by ASARCO but was not identified on the trips to the mine.
Atacamite - is reported by ASARCO and many specimens of a green bladed mineral that were collected on early trips to the mine were identified as atacamite, but I have x-rayed a number of these
specimens and the ones that I checked were all brochanite. Eriochalcite another copper chloride has been identified from the mine, and it may have given a test for chloride and been identified as atacamite. There is a large deposit of atacamite a few miles away, but it is deep and only been located by drilling.
Azurite - certain areas of the dumps are relatively rich in narrow veins and coatings of azurite.
Barite - is an uncommon secondary mineral found mainly with chrysocolla. In the two trips by the Foundation, three specimens of small less than a quarter inch crystals were found.
Bornite - was found by ASARCO in the sulfide concentrates but not seen in hand specimens.
Brochantite - is the most common of the secondary copper minerals and occurs as green coatings and sprays of crystals.
Chalcocite - forms as a replacement of pyrite and chalcopyrite in the supergene zone and was the ma

jor copper ore mineral at Sacaton.
Chalcopyrite - masses of chalcopyrite are found with pyrite.
Chrysocolla - another common secondary mineral found as small veinlets and coatings.
Copper - is found as thin sheets up to several inches across.
Covellite - forms with the chalcocite as sooty coatings on pyrite.
Cuprite - is found as octahedrons and cube-octahedron combinations up to a quarter of an inch. They are altered to malachite on the surface
but the cores are fresh cuprite.
Eriochalcite - found as a blue crust that forms a coating on chalcocite. It may be forming in the dump at present. It is mixed with brochantite.
Jarosite - found as massive yellow brown coatings and small sharp dark brown crystals.
Malachite - found sparingly with azurite and cuprite.
Molybdenite - is reported by ASARCO but was not identified on the trips to the mine
Neotocite - is reported by ASARCO and a fair amount of black resinous to vitreous material was noted on the trips. This material has been called tenorite or a black manganese mineral and is probably the material reported as neotocite.
Pyrite - thick veins up to several inches across of pyrite are present. Many of these are partially altered to chalcocite. The two form a mixture of black and brass colored material that can be cut
into cabochons.
Sphalerite - was found by ASARCO in the sulfide concentrates but not seen in hand specimens.

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