Copper Minerals from Arizona. 275 



XIV. — On Remarkable Copper Minerals from Arizona. 



BY GEOKGE F. KUXZ. 

 Read October 5, 1885. 



Some of the recent output at the Arizona copper mines equals 

 in beauty any heretofore found in the United States, and these 

 mines bid fair to outrival the world in the perfection of their 

 mineral yield. Among the principal varieties are azurite, mala- 

 chite, chrysocolla, native copper, and cuprite. Although the 

 azurites are not equal to the finest from Chessy, still they do not 

 appear to disadvantage in the comparison. The malachite is 

 not abundant, but considered as single specimens, it is hardly 

 inferior to that from Siberia. 



Malachite. 



This mineral, from the Copper Queen mine at Bisbee, Ari- 

 zona, in beauty and thickness of vein almost equals the Russian. 

 One mass, in particular, weighing 15 lbs., would furnish a 

 magnificent table-top of no mean dimensions. Its measure- 

 ments are: Length, 20 cm.; width, 15 cm.; height, 15 cm. 

 It is covered throughout with mammillary protuberances mea- 

 suring 35 mm. Among other pieces of peculiar interest, one, 

 weighing 14 lbs., has a vein several inches in thickness and a 

 surface roughened with mammillary knobs, the result of radia- 

 tions 2.5 cm. across. On this there is a stalactite projecting as 

 much as 10 cm., and from 2.5 to 4 cm. in diameter. Another 

 specimen with a mammillary surface has a dozen stalactites, 

 measuring from 10 to 20 mm. in diameter, and 5 cm. in height. 

 We also have malachite in seams, 7.5 cm. thick, and sometimes 

 30 cm. square, covered on both sides with mammillary tufts of 

 malachite, so compact as readily to admit of a polish. In addi- 

 tion to these, there are wonderful pockets of transparent cal- 

 cite and malachite, measuring 10 to 20 cm. in width, filled 

 with tufts of brilliant green, transparent, acicular crystals of 

 malachite from 5 to 10 mm. 'long, grouped with beautiful 



