PETROLOGICAL ABSTRACTS AND REVIEWS 323 



EiTEL, W. "tjber das Vorkommen von Zinkblende im Basalt des 

 Biihls bei Cassel," Centralhl. f. Min., etc., 1920, pp. 273-85. 

 Figs. 6. 

 Describes the occurrence of zinc blende in basalt. At an unknown 



depth, the erupting basalt broke through dikes of blende with a httle 



pyrite and much quartz. Included fragments of the dike rock were 



assimilated and recrystallized. 



EiTEL, W. "Bemerkungen zu einer Untersuchung von Lewkonja 

 liber die von Horns tein im Basalt des Biihls bei Kassel gefun- 

 denen Eisenknollen," Senckenbergiana, Vol. II (1920), pp. 

 ^3°-33- Figs. 2. 

 Native iron, from the basalt of the Biihl, near Cassel, is described. 



EiTEL, W. "Bemerkungen zu chemischen Untersuchungen des 

 Herrn F. Flade iiber das Eisenvorkommen im Biihl bei Cassel," 

 Senckenbergiana, Vol. II (1920), pp. 158-63. 

 Gives an early (1909?) chemical analysis of the Biihl native iron. 



EiTEL, W. "Studien iiber die Genesis der Einschliisse des Biihl- 

 basaltes," Abhandl. d. Senckenbergischen Naturforsch. Gesellsch., 

 Vol. XXXVII (1920), pp. 139-76. Figs. 29. 

 Among the separate studies in this paper are the following: On 

 pseudomorphs of pyrrhotite after pyrite in the Biihl basalt; on the 

 origin of the magnetite inclusions in the Biihl basalt; a comparative 

 study of the native iron from Ovifak and Biihl; on the genetic relation- 

 ship of the native iron to the inclusions of pyrrhotite and magnetite; 

 the relationship between the strata penetrated by the Biihl basalt and 

 the inclusions in the latter; experimental studies on the formation of 

 pyrrhotite from pyrite at high temperatures; on the occurrence of a 

 sillimanite-graphite rock with pseudomorphs of spinel, rutile, and 

 enstatite after garnet as an inclusion in the Biihl basalt; and the gas 

 reactions in the Biihl basalt and their role in the origin of the native iron. 



EsKOLA, Pentti. "The Mineral Facies of Rocks," Norsk, geol. 

 tidskrift, Vol. VI (1920), pp. 143-94. 



Metamorphic rocks, by recrystallization, may arrive at a state of 

 chemical equilibrium. The term "metamorphic facies" is here used to 

 designate a group of rocks characterized by a definite set of minerals 



