Alnoitic Rocks at Isle Cadieux, Que. 7 



For the analysis (I, Table I) and for the other analyses 

 in this paper I am indebted to Dr. Washington and take 

 this opportunity of expressing my thanks. 



Table I. 





I 



II 



Norm of I* 



SiOo 



33.26 



30.85 



An 



8.06 



Al 9 6 3 



5.90 



8.21 



Kp 



1.93 



Fe 9 3 



5.30 



3.33 



Ne 



5.68 



Feb 



6.54 



6.52 



Ol 



49.56 



MgO 



26.41 



23.16 



Cs 



15.82 



CaO 



14.47 • 



16.46 



Mt 



7.66 



Na,0 



1.23 



1.01 



11 



4.10 



K 2 



0.82 



1.43 



Ap 



2.02 



H,0 + 



1.91 



1.22 





Symbol 



H 2 — 



0.09 



0.05 



IV" 



(1)2.5.2.1 



C0 2 



1.10 



3.04 







Ti0 2 



2.15 



2.87 







Zr0 2 



none 



n.d. 





• 



PA 



0.76 



1.90 







MnO 



0.15 



0.21 







Cr 9 3 



0.05 



n.d. 







BaO 



0.08 



n.d. 







S0 3 



0.22 



n.d. 







100.44 100.26 



I. Monticellite alnoite (melilite-rich) Isle Cadieux, Quebec. 

 H. S. Washington analyst. 

 II. Monticellite alnoite (melilite-poor) Isle Cadieux, Quebec. 

 H. S. Washington analyst. 



* Calculated by Dr. Washington. The C0 2 indicates 2.50 per cent calcite. 



Under II in Table I is given an analysis of a variety 

 rather rich in monticellite and very poor in melilite. 

 This specimen was chosen for analysis partly in order to 

 have a chemical check upon' the optical identification of 

 the monticellite. The microscope shows the minerals to 

 be present in roughly the following proportions in weight 

 per cent : biotite 30, monticellite 25, ch^solite 15, augite 

 10, melilite 3, apatite 4, perovskite and ore 7, carbonates 6. 

 Though there are lime minerals other than monticellite in 

 considerable amount, they fail entirely to account for 

 the 16.5 per cent of lime shown in the analysis. About 

 one half the lime must be assigned to the monticellite 

 which checks approximately with the amount of monti- 



