Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/89

This page has been proofread, but needs to be validated.

that the veinstones on the east side of this fissure are soft, consisting of calcareous and fluor spars, as is the case in all the Weardale mines; but that on the west side, as at Coal cleugh, Kilhope, Aldstone, and in Teesdale, the matrix is hard, being composed of quartz, heavy spar, and pearl spar, together with much black jack or blende. This observation however cannot apply to the veins on the Derwent towards the east, or to those on Cross Fell towards the west; for in the former quartz passing into chalcedony is the most common matrix; and in the latter amorphous fluor prevails. Disintegrated fluor was the most common vein stone at Breckensyke mine, situated on the south bank of the Wear between 1 and 2 miles below Burtree-ford, which in 1803, when I visited it, produced more ore than any other in the district.

About 2 miles west of Burtree-ford dyke, Whetstone-mea vein crosses the mining field from south-east to north-west, and passes by Coal cleugh and Kilhope. Its north-eastern side is thrown up.

At Coal cleugh and Rampsgill, Bainder end vein is met with passing from north to south. The throw occasioned by this vein is 1 yard on the west side. At Coal cleugh Moss cross vein and Handsome-mea vein have been worked. The bearing of the first is north and south, and it is an upcast to the east of 6 fathoms. The second runs south-east and north-west, and throws up the sills 18 or 14 fathoms on the north-eastern side.

On Aldstone moor the wide open vein called White-heaps, from containing large quantities of spar, was formerly worked, but like most broad fissures proved unproductive, and has long since been abandoned. Little alteration was occasioned in the level of the strata by this vein, the range of which was south-east and north-west. Linn bank cross-vein, which passes from north to south, intersects it.