S. L. Penjield — Crystallized Bertrandite. 



213 



Art. XX Y. — Crystallized, Bertrandite from /Stonekam, Jfe., 

 and lit. Antero, Colorado ; by S. L. Fenfield. 



1. Stoneham, Maine. 



For the bertrandite from Stoneham, Me., the second locality 

 in the United States,* I am indebted to Mr. George F. Kunz 

 of New York. He states that, at the time herderite was 

 found and described by Mr. Hidden, f he noted the small 

 crystals occurring in pockets with the herderite and laid them 

 aside as an unknown mineral; the quantity was too small to 

 warrant any further investigation at the time. Becoming con- 

 vinced, after the identification of bertrandite at Mt. Antero,:{: 

 that his crystals were the same mineral he generously turned 

 them over to me for identification and description. Only a 

 few specimens were observed and the crystals were all small, 

 the largest of the three which were detached for measurement 

 being about 2 - 5 mm long by l-5 mm broad. The luster of the 

 faces is not very perfect and the measurements with the re- 

 flecting goniometer not as good as could be desired. The 

 habit of the crystals is unlike anything that has been pre- 

 viously described and as it throws considerable light on the 

 crystallization of the mineral is worthy of a detailed descrip- 

 tion. The forms which were observed were as follows : 



c, 001, 0; b, 010, i-i; h, 130, i-3 : d, 102, -J-i; e, 031, 3-1 and x, 162, 3-6. 



The simplest combination is shown in fig. 1, where the faces 

 c and d are prominent at one end of the vertical axis and o 



*In a letter, dated Sept. 26, 1888, Mr. W. E. Hidden announced to us that he 

 had identified bertrandite (or a new mineral) on specimens of herderite from 

 Stoneham. — Eds. 



f This Journal, III, xxvii, 135, Feb., 1884. flbid., Ill, xxxvi, p. 52, 1888. 



