Palache and Merwin — Connellite and Chalcophyllite. 539 



equivalents of water first given off are accounted for in our 

 formula : cupreous chloride volatilizes at a higher temperature, 

 and finally chlorine and sulphur trioxide are expelled. 



Penfield's analysis of connellite from Cornwall maybe repre- 

 sented by a molecular grouping of the same general form as 

 the above, but quite different in its proportions : 



[CuS0 4 .3Cu(OH) a .H a O].2[CuC] 9 .Cu(OH) a .H 3 0].7[Cu(OH)J. 



Chalcophyllite was identified in the specimen by measure- 

 ment of crystals, and by qualitative chemical tests for arsenic, 

 copper and aluminum. Most of the crystals were irregular 

 plates embedded in the connellite. The perfect basal cleavage 

 and rich green color were conspicuous features. A single 

 minute implanted crystal was obtained, which gave extremely 

 satisfactory readings for the forms c(0001), a? (1014), e (0112), 

 r (1011), and y (0221). Of these forms x is new, and y does 

 not appear in Dana's list, although given by Goldschmidt 

 (Winkeltabellen). The measured angles differ considerably 

 from those derived from Des Cloizeaux's element (crystals 

 from Cornwall), and a new ratio was therefore calculated, as 

 shown below: 



a : c = 1 : 2-554 p Q = 1*702 Des Cloizeaux. 



a : c = 1 : 2-671 p = 1*780 Palache. 



Calculated 

 Des Cloizeaux Palache Measured No. of faces 



Angle c^w "26°10' 27 c 12' — 



c^x 37 38 37°4l' 3 



G/^d 44 30 45 08 — 



c /v e 55 51 57 02 56 59 3 



c /s r 71 16 72 02 72 02 3 



c A y 80 48 81 01 2 



The measured crystal is of rhombohedral habit with the unit 

 form dominant and very small base. 



As this mineral was first mistaken for spangolite, it seems 

 worth while to note here the close similarity in .physical char- 

 acters existing between the two. Both are soft, dark green, 

 hexagonal with perfect basal cleavage, and optically negative. 

 Furthermore, the chalcojphyllite rhombohedrons have inclina- 

 tions to the base which are closely matched by pyramids occur- 

 ring on spangolite. 



tin fortunately there was not enough of this material for 

 quantitative analysis, which would have been desirable in view 

 of the uncertainty as to the composition of chalcophyllite. 



Considerable interest attaches to the occurrence of these 

 minerals at Bisbee, because of their association elsewhere with 



