S. L. Penjield — Canfieldite, a new Germanium Mineral. 107 



be found to contain positive melilite, still it is probable that 

 this variety of the mineral has a greater distribution than has 

 heretofore been supposed. Its occurrence in such abundance 

 in the Manheim dike adds interest to a rock in itself so rare as 

 to be worthy of special note. 



Of the other minerals in the rock the olivine, magnetite, 

 and perofskite show no unusual features and require no de- 

 scription other than that previously given. 



The mica, on examination in convergent light, proved to be 

 biotite. In view of the nature of the rock this result was 

 hardly to be expected, and it is probable that anomite is also 

 present, though not yet identified. 



Upon the basis of its mineralogical composition, and from a 

 comparison with a specimen from the type locality* the rock 

 must be classed as alnoite. The only respect in which it 

 differs very markedly from the rock at Alno is in the almost 

 complete absence of pyroxene. With this exception, sections 

 from the two localities are nearly identical in appearance. 



The same difference exists in greater degree between the 

 Manheim rock and the one other melilite rock thus far de- 

 scribed from this .country — the alnoite of Ste. Anne, Canada. 

 The latter rock also contains nepheline which has not been 

 found in the Manheim alnoite. Still, in spite of these dif- 

 ferences, the rocks are so closely related that there can be no 

 error in classing them together. 



Hamilton College, Clinton, N. Y., April, 1893. 



Art. XY. — On Canjieldite a new Germanium Mineral and 

 on the Chemical Composition of Argyrodite • by Samuel 

 L. Pexfield. 



It is with great pleasure that the author is able to announce 

 the discovery of a new mineral containing germanium and to 

 record the occurrence of this rare and interesting element from 

 a new locality. The credit of this is due in great measure to 

 the keen mineralogical interest of Mr. Frederick A. Canh'eld 

 of Dover, K. J., to whom, while on a business trip in Bolivia, 

 South America, some specimens of this mineral were given as 

 samples of a rich and unknown silver ore, by friends connected 

 with the mining industry. These were brought to the writer 

 for identification and he takes great pleasure here in acknowl- 

 edging his indebtedness to Mr. Canfield and in expressing his 



-Tornebohm, A. E. : Melilitbasalt fraan Alno; Geol. Foren i Stockholm For- 

 handl., 1882. vi. No. 76, p. 240. 



