576 



M. AU ROUSSEAU AND HENRY S. WASHINGTON 



The most noteworthy chemical characters of the nepheHte 

 syenite are its low silica percentage, the approximate equality in 

 amount of soda and potash, the high content of titanium and 

 zirconium, and the comparatively large amount of SO3 as compared 

 with chlorine. Though it undoubtedly belongs to the highly sodic 



TABLE I 



I. Nephelite syenite, Beemerville, N.J. M. Aurousseau, anal. 



II. Nephelite syenite, Beemerville, N.J. L. G. Eakins, anal. U.S. Geol. Surv. 

 Bull. 150 (1898), p. 211. 



III. Foyaite, Magnet Cove, Ark. H. S. Washington, anal. Jour. Geol., IX (1901), 

 p. 61X. 



IV. Lujavrite, Rabots Spitze, Kola. V. Hackmann, anal, i^ewma, XI (i894),p. 132. 

 V. Norm of I. Symbols, (I) II. 7. i'. 3. Janeirose. 



comagmatic region of the eastern United States, in these respects 

 it differs remarkably from the well-known nephelite syenites 

 of Massachusetts, Connecticut, New Hampshire, and Maine, and 

 also from the nearest similar exposure, that is, from the nepheHte 

 syenite of Brookville. The last-named rock resembles the nephelite 

 syenites of New England and shows the essential differences 

 between them and the Beemerville rock (see Table III). The other 

 nephelite syenites of the northeastern United States, and, in 



