Ford and, Bradley — Footeite and Connellite. 671 



servance of inclined extinction with an angle of 7-J° on a face 

 in the prism zone, and because of the arrangement of the ter- 

 minal faces, it was decided that the mineral had a monoclinic 

 symmetry. No goniometer measurements were made, but a 

 few angles which were obtained under the microscope were 

 recorded. Twins were observed which were said to be like 

 those of harmotone in habit. 



The pyrognostic properties were given as follows : When 

 heated in a closed tube the crystals became black without change 

 in form, and water was deposited in the upper part of the tube 

 with first a gray and then a green sublimate below it. In the 

 flame it gave the characteristic color of copper chloride. By 

 reduction on charcoal it gave a copper globule. It was easily 

 and quietly soluble in acids. 



A partial analysis was made upon a sample weighing only 

 0*0 165 g., only chlorine and copper oxide being determined. 

 The water present was not determined directly but was esti- 

 mated by difference. Under the circumstances of the analysis 

 it is not surprising that the small amount of sulphuric acid 

 present should have been overlooked. The analysis by Koenig 

 is quoted later. 



It was found on a new study of the original footeite material 

 that there was an error in the determination of its crystal lo- 

 graphic symmetry as made by Koenig. A section cut perpen- 

 dicular to the prism zone showed under the microscope in 

 convergent light a normal uniaxial interference figure with 

 optically positive character. Also the prismatic sections were 

 always found to show parallel extinction. The crystal system 

 is therefore hexagonal, since Koenig in his description notes 

 the apparent hexagonal symmetry. This agrees w T ith the de- 

 scription of the better crystals of connellite from Cornwall. 



New occurrence of Connellite from the Bisbee district. 

 The connellite, to be described, w r as found at the Czar mine at 

 Bisbee, Arizona. It occurs as small radiating masses of very 

 slender to capillary prismatic crystals which lie in cavities of 

 massive cuprite. In some cases the crystals are separated from 

 each other, and in other cases they lie close together forming 

 a radiating prismatic mass. The cuprite is of exceptionally line 

 quality, the grains being in places quite transparent. Occa- 

 sional^ in the cavities of the massive mineral small brilliant 

 cubic crystals were observed. Malachite with a delicate radi- 

 ating fibrous structure, massive azurite and chrysocolla occur 

 in smaller amounts. On two specimens minute grains of spang- 

 olite were observed. This rare mineral was identified by its 

 color, cleavage, and optical characters. Intimately associated 

 with the connellite and usually as a thin layer between it and 

 the cuprite occurred a bluish white clay-like mineral which 



