ON THE BARYTES MINES NEAR BANTRY. 



BT 



EDWARD T. HARDMAN, F.C.S., of the Geological Survey of Ireland. 

 [Read January 21st, 1878.] 



Sulphate of Barytes or Heavy Spar is a mineral of not very 

 common occurrence in Ireland, and is only met with in a few 

 localities in sufficient quantity to be of commercial value. In 

 various places in the county Cork it is found in some abundance ; 

 and near Bantry it has been, and I believe is at present, being 

 extensively worked. Having visited these mines some time ago, I 

 propose giving a brief description of them. 



The most extensive lode is met with in the townland of Derry- 

 ginah, Middle, about two miles east of Bantry. It bears nearly 

 due east and west, N. 80° E. & S. 80° W. ; cutting the strike of 

 the Old Red Sandstone slates, at an angle of about ten to fifteen 

 degrees. The lode is ten to fifteen feet thick, and has been fol- 

 lowed for some 200 or 300 yards, the workings extending to a 

 depth of about fourteen fathoms. About one-third of the lode in 

 the centre consists of extremely pure Barytes, but the sides of it 

 consist of an impure variety called cawk, which contains a quan- 

 tity of quartz, carbonate of lime, green carbonate of copper, 

 Peacock copper ore, and micaceous or specular iron. The last 

 is found in considerable quantity — so much so, that the manager 

 of the works was of opinion it might prove commercially valuable 

 could it be smelted. 



Besides the difference in purity of the Barytes, two varieties 

 occur in this lode. One a crystalline glassy-looking specimen ; 

 the other a granular saccharoidal variety, and the last is the 

 kind most valued, as it is the most easily ground in the process 

 of preparation. 



From this mine a considerable quantity of mineral has been 

 obtained and exported by the Bantry Barytes Mining Company, 

 who are now working it. When in full work they can easily 

 turn out twenty tons per day. But the mine is capable of yield- 



