J. V. Lewis and L. H. Bauer — Cyprine. 249 



Art. XXV. — Cyprine and Associated Minerals from the 

 Zinc Mine at Franklin, N. J.; by J. Volney Lewis and 

 Lawsox H. Bauer. 



The following notes refer chiefly to cyprine, the sky- 

 bine variety of vesuvianite, in intimate microscopic mix- 

 ture with willemite, and to the associated rhodonite (var. 

 bustamite) and andradite (var. polyadelphite). 



1. Vesuvianite, var. Cyprine. — Blnish green fibrous 

 cyprine was found in granite in the Parker shaft, at 

 Franklin, in 1905, and was described by Professor 

 Palache, 1 who also published the analysis by Steiger, 

 which is quoted below for comparison. 



The mineral here described was found in the ore body 

 near the hanging wall in a crosscut 374.5 feet south and 

 361.5 feet west of the Parker shaft, and 10 feet above the 

 850-foot level. It is sky-blue in color ; in texture it varies 

 from fine granular and fibrous to dense. To the naked 

 eye, and even under the hand lens, it appears to be homo- 

 geneous. The analysis (A, below) showed nearly 22 per 

 cent, zinc oxide, and since the oxide ratios fell within the 

 limits of variation of vesuvianite, it was supposed that 

 a new variety of this mineral had been found. 



Thin sections showed, however, that while vesuvianite 

 is the dominant mineral, it is plentifully sprinkled with 

 rounded grains and hexagonal crystals of willemite, with 

 dimensions up to .16 mm. in diameter. Measurements 

 by the Rosiwal method showed that this mineral consti- 

 tutes 29 per cent, of the volume, or 33.3 per cent, of the 

 mass. If the zinc, iron, and manganese of the accom- 

 panying analysis (A) are assigned to willemite, the cal- 

 culation gives 32.68 per cent, of this mineral. The 

 remaining constituents, calculated to 100 per cent., repre- 

 sent approximately the composition of the vesuvianite. 

 A few minute particles of metallic copper were visible 

 under the microscope, but doubtless most of the copper 

 determined is in combination. 



The analysis of this mixture and the results of the 

 calculations are given here, together with Steiger 's 

 analysis 2 of cyprine from the Parker shaft. 



1 Charles Palache : Contributions to the Mineralogy of Franklin Furnace, 

 this Journal, (4), 29, p. 184, 1910. 



2 U. S. Geol. Survey, Bulletin 591, p. 315, 1915. This statement of 

 Steiger 's analysis, which is followed here, differs slightly from that given 

 by Professor Palache. 



