60 Dr Boue on the Geography and Geology of 



Old mines are still to be seen there. Compact limestone occurs 

 on both sides of this porphyry, which constitutes the Malo 

 Sturacz. 



A great deposit of sienitic porphyry with breccia constitutes 

 both of the steep banks of the Ibar, near Rudnitza ; and, as in 

 Hungary, trachytes are not far from it. A much more exten- 

 sive sienitic porphyry formationo ccupies the whole neighbour- 

 hood of Karatova in Macedonia, and is surrounded by mica- 

 slate and talcose rocks, and hills of trachyte and trachytic con- 

 glomerate. The porphyry is generally greyish or bluish, very 

 often containing crystals of hornblende, more rarely of augite. 

 It occurs in a decomposed and earthy form in the neighbour- 

 liood of the singular town of Karatova, which is situated upon 

 three or four ridges of porphyry, separated from each other by 

 deep and steep ravines. Some brecciated or tufaceous porphy- 

 ritic masses are associated with it ; indeed the porphyry seems 

 occasionally to be in broad dykes, with salbandes of breccia 

 containing fragments of slaty rocks, as also of porphyr3^ An 

 example of this is seen one league to the W. of Karatova, in 

 the valley of Braunitza. Ascending from that town to the 

 south, we leave the decomposed, sterile, greyish-blue por- 

 phyry, and meet with unaltered rocks, which establish the con- 

 nection between the secondary porphyry and some trachytes, or 

 even phonolites. Breccia is also seen here and there, but all 

 the relations of the rocks are obscure in this wild country. All 

 that can be said, is, that masses or hills of porphyry with coni- 

 cal or table-shaped summits arc placed next each other. 



At 1 ^ leagues S. W. of Karatova, a mine has been establish- 

 ed in some small veins containing argentiferous galena, associ- 

 ated with a little quartz, carbonate of lime, and hydrate of iron. 

 These veins are found in a particular zone of the porphyry, run- 

 ning E. — W. ; and the rock is, as in Hungary, siliceous near 

 the vein, and of a whitish or greyish colour. The surface por- 

 tion of the metalliferous stripe has been excavated in an unskil- 

 ful manner, and the mines, which are provided with a large 

 pit, are not well managed. In the smelting-house the ores are 

 roasted and smelted in such a way that I observed, in the heaps 

 of scoria, a quantity of galena nearly in its original state. 



Pet haps few geologists will agree with me in separating these 

 metalliferous porphyries from the trachytes, because they cannot 



