Kinahan — On Granite and Metamorphic Rocks. 219 



clasic granite, and the varieties of oligoclasic granite so varied in 

 texture, colour, and beauty. 



The prevailing colour of the mass of the porphyritic oligoclasic 

 granite is mottled pinkish, with smaller white and greenish crystals 

 of felspar, and larger crystals, often twins, of flesh-coloured felspar, 

 which give the rock its porphyritic character. Conspicuous acces- 

 sories in this rock are titanite (sphene) and blackish hornblende. 

 Towards the west of the county there is a less coarsely and more 

 evenly crystalline oligoclasic granite (Omey type), in which titanite 

 and hornblende rarely occur. In places, coming up through these 

 oligoclasic granites, the gneiss and the schist, there are the ordinary 

 light-grey or whiteish Orthoclasic granites, sometimes forming tracts, 

 as in the neighbourhood of Oughterard. 



In the north-west of the Co. Galway, near Kylemore, at Lug- 

 nanoon, there is a mass of much newer oligoclasic granite, 

 graduating into elvan, it being of the same age as the sheets of 

 euryte [Bundorragha euryte), in the Silurian rocks [Mweelrea and 

 Slieve Partry beds). 



[At Lugnanoon, Omey Island, Illaun M'Dara, and neighbourhood, very long blocks 

 of large scantling might be raised ; those in Illaun M'Dara and in Omey Island bein<'- 

 very easily procured. 



The boulders found on the Galway tract of granite extending from Lough Corrib 

 westward to Kilkieran Bay are of very great magnitude ; so that blocks of all probably 

 required sizes could be obtained from them. Some of these boulders have undoubtedly 

 split up since being left in their present position ; but the majority of them, some of 

 vast size, are as sound now as when the ice deposited them.] 



Galway quarries. As has just been mentioned, the granites, 

 elvans and porphyries are greatly varied in texture, colour, and 

 beauty. These have been brought lately into the market by the 

 Messrs Millar, of the " Galway Marble and Granite Works," who 

 are prepared to supply obelisks, columns, dies 3 to 4 feet square, 

 caps, bases, headstones, and all kinds of monumental and other 

 cut-stone and polished work. At present they can raise blocks 10 

 feet long by 2 to 3 feet square, and slabs from an inch upward in 

 thickness, 9 feet long and 3 feet wide. The principal quarries 

 now being worked are : — 



No. 1, St. Helen's, Taylor's Rill. — Fine-grained; red, clouded 

 with yellow, maculated with black and a little white ; polishes well ; 

 can be got in blocks from 5 to 7 feet long; a very serviceable stone 



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