THE OCCURRKNCE OF ALLANITE IN CANADIAN ROCKS. 103 



NOTE ON THE OCCURRENCE OF ALLANITE IN 

 CANADIAN ROCKS. 



BY E. J. CHAPMAN, Ph.D. 



PEOFESSOE 01? MINEEALOGT AND GEOIOGT IN UNJVEESITT COLLEGE, TOEONTO. 



(Laid before the Canadian Institute, February 20, 1864.) 



The minei'al Allanite or Orthite is a comparatively rare species. 

 Tip to the present time, the only announcement of its occurrence in 

 Canada, is contained in the following brief notice by Prof. Sterry 

 Hunt, given in the last Report of the Survey (1863.) 



" Ceeium : — Some small crystals of a mineral having the aspect of Allanite 

 were found in a feldspathic rock near Bay St. Paul, and gave by analysis a 

 portion of oxide of cerium with lanthanum. Minute crystals of a similar 

 mineral have been observed in a rock composed of labradorite and hypersthene, 

 from Lake St. John." 



In a collection of specimens, obtained from the Muskoka district of 

 Upper Canada by Mr. II. White, P. L. S., and lately submitted to me 

 for examination, I found a number of sharp-edged fragments of a 

 black amorphous mineral, which proved to be a compact variety of 

 allanite. These fragments had much the appearance of anthracite 

 coal, or pitchstone. Some of them were as large as hazel nuts, and 

 the whole weighed over two ounces. They were obtained, according 

 to Mr. White and his son, from a vein an inch or more in width, at 

 Hollow Lake, the head-waters of the South Muskoka. This lies far 

 within the Laurentian area ; but I am unable to ascertain whether the 

 vein occurs in an ordinary gneiss rock, or in one of the anorthosites 

 of the upper part of the Laurentian series. 



The presence of this mineral, in such comparative abundance, in 

 our Laurentian rocks, is a fact of some interest ; and I have therefore 

 thought it desirable to insert a short notice of the discovery in the 

 Canadian Journal. 



The allanite of this locality constitutes a somewhat distinct variety, 

 characterized more especially by its want of crystallization. It appears 

 to resemble the variety from East Bradford, Chester County, Pennsyl- 

 vania, analysed by Rammelsberg, {Mineral chemie, 744, 746), and that 

 from Monroe, Orange County, New York, examined by Genth {Am. 



