Geological Relations of the East of Ireland, 171 
which is quarried. Beyond the greenstone, clay slate re-appears in 
mass for a considerable way : all these rocks ranging north-east and 
south-west, and dipping 65° to the south-east. 
In descending the river by the same bank we find the granite 
immediately succeeded by clay slate and quartz rock ; both of which 
contain here and there crystals of felspar: and these two rocks, 
either pure or intermixed in various states of combination, occupy 
the remaining part of the course of the Avonmore to its junction 
with the Avonbeg; and thence downward, in both banks of the 
Ovoca to Newbridge, ranging on the northward through Tigrony, 
Cronebane, Connery, and Kilmacow, toward the eastern part of 
West Aston ridge, and to the southward passing into Knockanode, 
Kilcashel, Ballymurtagh, and Ballygahan ; (see PI. 8. No. 7.) 
§ 62. Cronebane is flanked on the north-western and south- 
eastern sides, in Connery and Tigrony, by quartz rock; which 
varies from granular to compact splintery, and abounds in contem- 
poraneous veins of pure white quartz. The interval is occupied in 
part by pure clay slate, but principally by clay slate in almost every 
stage of union with quartz, from the large compressed lenticular 
nodules of quartz, terminating in thin edges and diffused between 
the laminae of the rock, (in the direction of which they are dis- 
posed), to the smallest and most perfect intermixture and solution, 
graduating at length into a substance which has all the characters 
of hornstone and even of flinty slate ; and these again pass by a 
series of gradations into pure clay slate ; a progression which is re- 
peated likewise on the outer flanks of the quartz rock. These 
quartzose varieties of clay slate abound in contemporaneous veins of 
pure quartz, which are more or less metalliferous. The quartz 
rock itself sometimes passes, though rarely, into red jasper, and even 
into chalcedony, as in Tigrony. 
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