Local Coal Mines
In a booklet published in 1861 by Thorn's, printed for Her Majesty's Stationary Office and titled "Explanations to accompany Sheets 163, 174 and part of 175 of the maps of the Geological Survey of Ireland", we find the following (pages 30-2): -
"Coal-pits, Duarrigle and Lisnashearshane Collieries
T h e s e c o l l i e r i e s a r e s i t u a t e d a b o u t 3 1 / 2 m i l e s N . N . W . o f M i l l s t r e e t a n d a m i l e S . W of Cleanrath. In Coal-pits, a little to the S.E. of Church Hill, three beds of coal were formerly worked. Two of these are supposed to be the Sweet2 5 and Rock veins,2 6 and the highest may be the Needle vein. To the N.E. of these, on the south of Mount Justice, in the townland of Knocknagarrane, a coal was also worked which seems to be the Castle or Morgan's vein.2 7 In Lisnashearshane and Duarrigle three beds of coal were also worked that lie to the south and appear to be higher than those in the Coal-pits. The lowest of these is a very small pindy vein and was only worked along its outcrop. The second was proved, or worked, from the road that runs north and south through the townland of Coal-pits, in a N.E. direction, to the eastern boundary of Duarrigle, where it turned and ran nearly E. and W. till it was cut off by a nearly N. and S. fault, a downthrow to the East,2 8 that is situated about 340 yards to the east of the bounds of Duarrigle. The vein was from sixteen to twenty inches thick, with a 'dog'2 9 two inches thick in the centre of it. Half of it was often coal, the rest culm. Under it was a 'seat' (fireclay and clunch) and over it a slate in which fossil ferns are found.3 0 The highest coal was worked a little in Duarrigle and 'proved' in Lisnashearshane. It was from two to three feet thick, on a fireclay, with a rock roof. Further south-west, in the strike of these beds, and half a mile due east of Duarrigle Castle, there were a few pits sank on a coal; and a mile to the S.W. of these pits Mr. Foot records a coal that is exposed in the River Blackwater. They seem likely to be the continuation of one of the beds in Duarrigle colliery. A coal smut is also exposed in the bank of the same river, two miles South East of Duarrigle Castle, and immediately west of Flintlfield House. .
2 5 The "Coal" or "Sweet Vein" - so called because the part first discovered was nearly free from iron pyrites and entirely coal. It is usually a coal; when not a coal, it is a good strong culm.
2 6 "Rock Vein" - this bed has usually a rock roof, from which its name. It is generally a culm but sometimes partly coal. Through this vein there is generally a "dog" - a streak of carbonaceous black shale that runs irregularly in the bed.
2 7 "Morgan's" or "Castle Vein" has received its name "Morgan's" from a man by whom it was first worked and "Castle" from having been worked under Dromagh Castle. It is a pindy and was therefore never extensively worked.
It is worthy of note, as a remarkable fact, that all the N. and S. faults that are proved are downthrows to the E. or upthrows to the W. 28
2 9 "Dog" is a thin layer of clunch or grit found in some of the coal beds. This is the only coal roof in which ferns were remarked, and here they seem to be numerous; but on account of the decomposed state of the shale it was impossible to get any good specimens. 30