450 Pirsson and Washington — Geology of New Hampshire. 



sections. In the lassenose marginal facies of the massif, as 

 noted above, it becomes quite abundant. 



In addition to the above, two or three small sections of an 

 indeterminable brown mineral were noted. It is strongly 

 pleochroic, varying from a clear chestnut brown to practically 

 opaque, like senigmatite. The refractive index is about that 

 of hornblende ; birefringence not high, but as the sections 

 are cut nearly perpendicular to an optic axis whose bar crosses 

 the. field, in conjunction with the deep absorption, this cannot 

 be well told, nor can any other optic characters be determined. 

 The bar crosses the field without apparent bending, but it is 

 not certain that the mineral is uniaxial. The color is unusual 

 for tourmaline, the absorption too strong for cassiterite ; if 

 biaxial the color and absorption much deeper than ordinarily 

 seen in allanite and much like that of senigmatite, but the 

 mineral associations scarcely suggest the latter. It seems most 

 probable that it is an unusually deep-colored allanite. 







Analyses 



OF PULASKX 



)SE, ETC. 









I 



II 



III 



IV 



V 



VI 



SiO„ 



60-75 



60-20 



65-54 



63-71 



63-20 



1-013 



Al o 3 ._._ 



19*08 



20-40 



17-81 



18-30 



17-45 



•193 



Fe 2 3 .__. 



1-54 



1-74 



0-74 



2-08 



3-60 



•010 



FeO 



2-98 



]-88 



1-15 



2-52 



n. d. 



•041 



MgO 



0-81 



1-04 



0-98 



0*09 



0-75 



•020 



CaO 



2-29 



2-00 



1-92 



1-18 



1-40 



•041 



Na 2 .... 



4-89 



6-30 



5'55 



6-39 



6-90 



•079 



K 2 G 



5-90 



6-07 



5-58 



6-21 



5-88 



•063 



H 2 OllO° + 



0-08 



0-23 



0*54 



0-17 



0-50 







H a O 110°- 



0*24 



o-io 







0'09 











co 2 







none 













- _ . 



Ti0 2 



0-63 



0-14 



0-11 



tr. 



0-46 



•008 



PA 



tr. 



0-15 



tr. 















so 3 





0-13 















_ _ 



CI 



. 



0-09 















MnO _... 



tr. 



tr. 



tr. 



tr. 











Total 99-79 100-47 99'92 100*74 100*14 



I. Pulaskose (syenite). West slope of Mt. Belknap, N. H. 

 Washington analyst. 



II. Pulaskose (pulaskite). Fourche Mountain, near Little 

 Rock, Arkansas. Washington analyst (Jour. Geol. ix, 1901, p. 

 609). 



III. Pulaskose (syenite). Highwood Peak, Highwood Mts., 

 Montana. Pirsson and Mitchell analysts. (This Jour, i, 1896, p. 

 295.) 



IV. Phlegrose (pulaskite). Salem Neck, Essex Co., Mass. 

 Washington analyst. (Jour. Geol. vi, 1898, p. 806.) 



V. Nordmarkose (nordmarkite). Tonsenas, near Christiania, 

 Norway. G. Forsberg analyst. (Brogger, Zeitschr. Kryst. xvi, 

 1890, p. 54.) 



VI. Molecular ratios of No. I. 



