THE OCCURRENCE AND PROPERTIES OF CHLOROPHO- 

 ENICITE, A NEW ARSENATE FROM FRANKLIN, NEW 

 JERSEY 



By William F. Foshag, 

 Assistant Curator, Department of Geology, United States National Museum 



Harry M. Berman, 



of Harvard University 



AND 



Robert B. Gage, 

 of Trenton, New Jersey 



INTRODUCTION 



In a preliminary paper the writers ^ gave a short description of a 

 new arsenate collected at Franklin during the year 1923. This 

 mineral was found during mining operations between the 500 and 

 600-foot levels of the mine of the New Jersey Zinc Co. where it 

 occurred in the pillars of ore that were being taken out at that time. 

 Specimens of this arsenate were apparently very rare and all possible 

 specimens of the mineral were procured for study. In all about a 

 dozen specimens were obtained and several of the better ones were 

 sacrificed for a sample for analysis. A larger specimen from which 

 the material for analysis was taken is preserved in the United States 

 National Museum (No. 94964, U. S. N. M.). A number of crystals 

 from this specimen were taken for crystal measurement but better 

 ones were found on a specimen in the Holden collection of Harvard 

 University (No. 81224), the crystallographic data given being based 

 on these. 



This arsenate mineral proved upon chemical analysis to be new 

 and the name chlorophoenicite was given to it. The name is derived 

 from the Greek x^<^pos (green) and ipoiviKos (purple red) in allusion 

 to the remarkable property it possesses of changing its color from 

 light green in natural light to a light purphsh red in artificial light, 



OCCURRENCE 



The chlorophoenicite occurs in cracks in the franklinite-willemite 

 ore associated with tephroite, willemite, leucophoenicite, calcite, and 

 zincite. Of these minerals the chlorophoenicite is later than all the 

 minerals except the calcite. The sequence is apparently willemite 

 and tephroite-leucophoenicite-chlorophoenicite-calcite. The wille- 

 mite forms fine grained masses of minute acicular crystals. The 



1 Journ. Wash. Acad. Sci., vol. 14, pp. 362-363, 1924. 



No. 2669.— Proceedings U. S. National Museum, Vol. 70, Art. 20 



25756—27 1 



