404 Eggleston — Eruptive Rocks at Cutting sville, Vt. 





I 



II 



III 



IV 



V 



VI 



VII 



SiO, 



57-64 



55-68 



54-22 



5506 



55-46 



56-58 



5502 



TiO, 



015 



0-60 



0-38 





0-20 





0-36 



A1»0, 



23-31 



20-39 



20-20 



23-29 



24-49 



19-89 



20-42 



Fe.0 3 



1-22 



210 



2-35 



3-29 



2-63 



318 



306 



Feb 



0-55 



1-95 



102 



not det. 



106 



0-56 



1-82 



MnO 



010 



0-31 



019 





Trace 



0-47 



0-22 



MgO 



0-22 



0-80 



0-29 



Trace 



005 



013 



0-59 



CaO 



0-67 



1-92 



0-70 



1-4.6 



0-92 



110 



1-67 



Na,0 



10-48 



918 



9-44 



6-76 



9-78 



10-72 



8-63 



K-O 



509 



5-34 



4-85 



8-86 



516 



5-43 



5-38 



H,0 + 



0-24 



1-50 



5-57 



1-08 



007 



177 



2-77 



h;o— 



002 





0-42 











PA 



Trace 



006 



011 





Trace 





006 



co. 



None 





Trace 











ZrO, 



012 





- 











so 3 



Trace 





None 











CI 



0-02 





Trace 











F 



006 





Trace 











Gi 2 0, 



None 















BaO 



None 





Trace 











SrO 



Trace 







• 









FeS, 



008 















Fe,S a 



005 















LLO 



None 















Sum 



10002 



99-83 



99-74 



no- so 



99-82 



99-83 



100-00 



I = Tinguaite, type phase (miaskose) , Cuttingsville, Vt., H. E. 

 win, analyst. 

 II =r Tinguaite (laurdalose), Brome Mt., Quebec. 



III = Aegirite tinguaite (miaskose), Southboro, Mass. 



IV = Leucite tinguaite (beemerose), Serra de Tingua, Brazil. 



V = Tinguaite< (miaskose) , Gy. Szt. Miklos, Czanod, Siebenburgen. 

 VI = Tinguaite (laurdalose), Hedrum, Norway. 

 VII = Tinguaite (average of 15 analyses, B. A. Daly). 



Mer- 



II Quoted from Dresser, J. A., this Journal, vol. 17, p. 355, 1904. 

 Ill " " Clarke, F. W., TJ. S. Geol. Surv. Bull. 591, p. 



35 1915 

 TV, V, VI " " Washington, H. S., U. S. Geol. Surv., Prof. 



Paper 14, pp. 207, 213, 295. 

 VII " " Dalv, B. A., ' ' Igneous Eocks and Their Origin, ' » 



p. 35. 



The rock is a miaskose, with the following norm : 



Orthoelase 30-02 



Albite 36-68 



Anorthite 1-96 



Nephelite 27-55 



Diopside 108 



Magnetite 1-86 



Ilmenite -30 



Water, etc -59 



10004 



Comparison with the Brome Mountain tinguaite shows 

 one more proof of general chemical similarity between 

 the Monteregian eruptives and those at Cuttingsville. 



