Bisbee daily review., 1904-08-13

mixed with limonite bure crystall- inc masses of any size being compara- lively rare. In stope 27, in the south western part of the mine, gust above the second level distinctly crystalline cuprite was noted. associated with limonite. malachite. brochantite, me lsnoehalcite and a little quartz. At the time of the visit this was the only place in the mine in which any quan- tty of the mineral was seen in other than the prevalent impure earthly matter.
 In the Calumet & Arizona mine. however. new stopes had been opened in ore bodies containing cuprite in large crystalline masses, usually as sociated with native copper and in beautiful druses of ruby-red isometric crystals. usually in the form of simple cubes, or of cubes modified by the octahedron and dodechedron. It is particularly abundant in the fine stope on the 950-foot level about $50 feet northeast of the shaft where it oc- CUTS in glittering punches in the more earthly ore penetrated by dendritic masses of bright metallic copper and spotted with little vugs of acicular malachite. It has also been found on the s50-foot level in irregular punches surrounded by melanochal- cite, chrysocolla. malachite and cal cite.
 TENORITE-The crystalline form of black oxide of copper was not ob- served in the course of the present investigation. The earthy variety however, commonly known as mel aconite. occurs in some Of the sort clayey ores, usually mixed with the black oxide of manganese in the form of light sooty powder. Ore ot tnls character containing about 5 per cent of copper was observed on the 1Ooo' loot level of the Lowell mine. In the Calumet & Arizona mine, about 50 feet above the S50-foot level, there Is a natural cavern in limestone, whose damp walls are covered with a olacK moss-like botryoidal growth. Thls material is apparently still being de- posted. for the fragile stems o1 the den dritic afflorescence break OH os their own weight when they reach length of over 1-2 inch and the floor of the cavern is deeply covered with fluffy carpet of this black material, Inspection of the wall sshows that they are composed of alternating irregular ly overlapping layers of the black CT florescence with druses of calcite Chemical tests of the black material made by W. F. Hillebran shows that it is a mixture of the oxides of copper and manganese, probably melanconite and bog manganese. or wad. Ae- cording to Foreman J. c. Merrill some of this mixture contains as much as l5 per cent copper.
 Koenig in 1891 described some small black crystals from the Copper Queen mine. and concluded they were es- sentially a mixture of cupric and cu- prous oxides, and were tetragonal in crystal form. He considered that they represented a distinct mineral species, for he proposed the name paramelac- onite. It appears, however, that more chemical and crystallographic work is necessary before paramelaconite can take final rank as a species distinct from tenorite, the crystallograhpic symetry of which is still in doubt.
 FOOTEITE--This mineral a peep blue carbohydrate of copper occurring in minute monoclinic prisms implant- ed with paramelacocite in limonite. was rst described and named by Koe- mig from a specimen said to have come from the Copper Queen mine. Foote- ite is evidently a rare occurrence in the Bisbee mines and was not seen in 1902.
 GANGUE MINERALS-Of the va rious minerals associated with the ores. calcite, in its role of principal constituent of the limestone in which the important ore bodies occur. is the most abundant. It is seldom. however. that the mineral forms sO large a part of the altered limestone in the immediate vicinity of the ore as it does of the unchanged rock in which mineralization has not been active. As will presently be shown, II has been largely replaced in the pf1 cess of naturalization by pyrite, an- phibole. pyroxene, garnet chlorite, ouartz vesuvianite and other minerals
 In the form of stalacites, often beau tifully colored with salts Of copper. and in showy crystalline masses cal cite was abundant in the bodies Ot oxidized ore worked in the early days
 
 in the Copper Queen mine, and IS s,iii encountered to some extent within inc oxjdixed zones. It is rarely. however a conspicuous gangue mineral m th= ores now exploited.
 The oxidized pyritic ores. paiticu- 1srIv those too poor for working are intimately associated with several min erals chiefly silicates of calcium. magnesium. and aluminium in varyins proportions. which so far as observer occur only in crystals of microscope size Their Identification accord,a 5i' denends upon the nicroseopical in- yestigation of thin sections. Of these minerals probably the most common is inc calcium-magnesium. amphiecis sremolite usually occurring in ssgre oates of minute radiating prism 5 which under the microscope snow tht characteristic cross sections. cle was and optical properties of this min
 ~-oa~,v or unite as abun1ant