98 JOURNAL, R.A.S. (CEYLON). [VOL. II., PART I. 



different lines assumes the various names of Balais ruby, 

 Vermeil, and Rubicelle, by mixture with blue, passes 

 through divers colours, till it finally arrives at indigo blue, 

 which is frequently so deep as to be barely distinguishable 

 from black. 



This then is the Ceylonite, which more resembles a piece 

 of jet than any other mineral. As a gem it can hardly be 

 said to hold any rock. It seldom or never comes under the 

 hands of the jeweller, but I can conceive that it might be 

 very well adapted to be formed into mourning ornaments. 



Ceylonite belongs to formations of the primative class, as 

 will be seen from the position in which I found it. It is 

 said to have been found imbedded in calcareous spar, and 

 in adulasia, accompanied by magnetic pyrites and crystals 

 of mica ; but of the correctness of this I am not aware. 

 The crystals I met with were found in the low bank, both 

 in the small water-courses formed by the rain and (by 

 digging) apparently in situ within eight or ten inches of 

 the surface. Its matrix appears to be a compact gravel. 



The whole of the neighbouring rock belongs to the pri- 

 mary formation. On one side, at the distance of a couple 

 of hundred yards or so, a cut in the road exposes a mass of 

 gneiss (the predominant rock of the country), affording an 

 excellent view of its conformable strata, dipping con- 

 siderably towards the east. On the opposite, or western 

 side, at no great distance, is discovered a vein of graphic 

 granite, the characters of which are very beautifully and 

 distinctly marked. On each side, and in contact with it, are 

 veins of quartz and felspar, more or less commingled, as 

 also a vein of mica. These, as shown by the section which 

 has exposed them, stand nearly in a perpendicular position. 

 One is struck by the arrangement which seems to mark 

 the gradual weakening, on each side of the graphic granite, 

 of that agency or power of peculiar crystallisation, which 



