Vicinity of Dublin, 275 



Kilranelagh ; and, as at that place, are accompanied by quartz, often 

 of a similar greenish colour ; with the addition however of bluish 

 grey granular limestone, and a fibrous substance, not improbably tre- 

 molite, mixed with carbonate of lime. I have not seen any felspar 

 in the specimens from Donegal.* 



2. Grenatite. (Staurotide, Haiiy). This was detected by Mr. 

 Stephens in crystals in a micaceous compound of which I found 

 a specimen at the Glenmalur lead mines in the County of Wicklow ; 

 the crystals are small, but their colour, form, and characteristic cross- 

 ing are very distinct, and they are infusible before the blowpipe. 



3. Beryl. (Var. oi Emerald^ Haiiy). The precious beryl h.2LS been 

 found by Mr. Stephens and myself imbedded in granite, near Lough 

 Bray in the County of Wicklow. (Museum of Dublin College, 

 No. 39.) Mr. Weaver has discovered it in blocks of granite, near 

 Cronebane in the same county ; and I have found in the Dublin 

 mountains above Dun drum, specimens probably belonging to the 

 same species. 



4. ylndalusite. [Feldspath apyre, Haiiy). This has been 

 found by Mr. Stephens and myself, in very distinct specimens, on 

 the north-east side oi Douce mountain in the County of Wicklow, ap- 

 parently imbedded in the mica slate of which that mountain is 

 composed, and accompanied by quartz, mica, and a remarkable crys- 

 tallized substance hereafter to be mentioned. It differs from the 

 Andalusite of Spain and of Scotland, chiefly by inferior hardness ; 

 for although some pieces scratch window-glass, others yield easily to 

 the knife : but the Count de Bournon has observed an equal vari- 

 ation in the hardness of specimens of this substance found by him at 

 Forez ;* and I have found that of the Scottish stone to vary very 

 much. 



' Since this paper was written, I have fonnd that this compound from Donegal has 

 been described b^ Mr. Sovrcrbj. British Mineralogy, August, 1810. p. 133. 



2m 2 



