SECTION III, 1886. Perl TRANS. Roy. Soc. CANADA. 
VII.—On Some Canadian Minerals. 
By B. J. HARRINGTON, B.A, PH.D., F.G:S. 
(Read May 26, 1886.) 
I.—SODALITE. 
The mineral sodalite, though not the only silicate containing chlorine, is interesting 
on account of the considerable proportion of that element which it holds. Its occurrence 
in Canada was first noticed by Dr. Hunt, who, many years ago, detected it in small 
quantity in the nepheline-syenite (granitoid trachyte of Hunt) of Brome Mountain. Subse- 
quently it was found by the writer in some of the nepheline-syenites of Montreal and 
Belæil, and more recently it has been discovered by Dr. G. M. Dawson on the Ice River, 
a branch of the Beaver Foot River, near Kicking Horse Pass, in the Rocky Mountains. 
The mineral from Montreal was described by the writer in 1875, and lately that 
from the Rocky Mountains has been examined. In both cases the results of analysis 
agree closely with the formula 3Na,A1,Si,O, + 2NaCl, and are as follows :— 







| CONSTITUENTS. | MONTREAL. Ice River. | FoRMuLA. 
| Silica.......................... 37.52 37.50 37.1 
| Nm e dobauooovro ddobcutocovda 31.38 31.82 31.7 
IMFerric oxide... tr. 0.01 
| Iiiben\oSacos scoala caboabcouabodd seis «Wi one 
IMNTagnesia ce --rreecerete A LE HEAR | 
| OD Alero re oie) er-iols/e oyaleiaisielsletel=lsionstalel= | 19.12 19.34 19.2 | 
| Potash.... ..................... | 0.78 0.27 | 
SaCliitinsooo ance Goer Sr ntoo.LandoD 4.48 4.61 | 4.7 | 
(Glalllaratity coog soncgond005e0 congas 6.91 Tel? 729 
| 
ToraL........... 100.54 100.67 100.0 | 
Specific Gravity-..........2....- 2.220 2,993 | 
l | 




Both varieties are of a fine blue colour, and that from the Rocky Mountains might be 
employed for the purposes of jewelry. A very beautiful polished specimen of it may be 
seen in the museum of the Geological Survey at Ottawa. The hardness in each case is 5.5. 
Sec. III., 1886. 11. 
