448 Hoffmann — New Mineral Occurrences in Canada. 



yellowish-green. In fine powder, it is easily and completely 

 decomposed by hydrochloric acid, with separation of gelati- 

 nous silica. 



The mean of two very closely concordant analyses, con- 

 ducted by Mr. Johnston, showed it to have the following com- 

 position : 



Silica _.. _ 36-94 



Boron trioxide __ 22-37 



Lime . _ 34-90 



Alumina 0*12 



Ferric oxide 0-02 



Magnesia _ 0*05 



Water (direct estimation) _____ 5*68 



100-08 



2. Faujasite. 



This species, which has been briefly alluded to in the pre- 

 ceding note as being one of> the mineral associations of the 

 datolite, found at the Daisy mica mine, on lot nine of the first 

 range of the township of Derry, Ottawa County, in the Prov- 

 ince of Quebec, is there met with in the form of simple octa- 

 hedral crystals implanted upon the walls of small cavities in 

 the quartz or intimately associated with the fluorite (in some 

 instances being, indeed, included in crystals of the latter min- 

 eral), both of which enter largely into the composition of the 

 matrix of the datolite. The crystals yary in size from such as 

 are of almost microscopic minuteness to others having a diame- 

 ter of about two millimeters. They are mostly milk-white — 

 with, in some instances, a faint greenish tinge, in color, and 

 opaque, occasionally, however, colorless and translucent, and 

 have a vitreous luster. In the closed tube the mineral yields 

 much water. Before the blowpipe, it intumesces and fuses to 

 a white blebby enamel. It is decomposed by hydrochloric acid 

 without gelatinization. An analysis of the same has been 

 entered upon. 



