466 C. J. WOODWABD ON A GEOUP OF 



25. On a Group of Mieeeals from Lilleshall, Salop. By C. J. 

 "Wooewaed, Esq., B.Sc, F.G.S., Lecturer on Chemistry and 

 Physics, Birmingham and Midland Institute, Birmingham. 

 (Read May 9, 1883.) 



The Carboniferous Limestone at Lilleshall has for very many years 

 been worked, partly as a flux for iron-smelting, partly as a source 

 of lime for agricultural purposes. 



Yarious workings in the neighbourhood have, from influx of water, 

 been abandoned ; and there remains now but one mine, known as 

 Stump Leasow*. It is situated by the canal, near a spot marked 

 " Old Farm " on the one-inch Survey map. 



There are two distinct beds of limestone, known as White and 

 Grey, lying one above the other, separated by a distance of 40 yards. 



The upper bands of the lower bed, or grey, are full of vertical 

 joints, which in many cases, speaking from memory, run from six 

 inches to a foot in width. It is in these joints that the minerals 

 occur. 



I have met with the following mineral species, put approximately 

 in the order of frequency or abundance, commencing with the least 

 frequent : — 



Quartz. Hasinatite. 



Erubescite. 

 Copper pyrites. 

 Iron pyrites. 



Barytes. 

 Calcite. 

 Dolomite. 



Quartz is extremely rare. I have, in fact, met with but one 

 minute crystal. It showed under the microscope both prismatic 

 and pyramidal faces. 



Erubescite. Only a few minute patches in the massive form have 

 been met with. 



Copper Pyrites is met with occasionally. It occurs in more or 

 less defined spheroids. One specimen has a peculiar radiated 

 structure. 



Iron pyrites is not by any means common. It occurs in radiating 

 masses of from § to 1| inch diameter, showing faces of the cube, 

 octahedron, and other forms. I have one specimen of the decom- 

 posed iron pyrites, which in old mineralogical books is called 

 " hepatic pyrites." This hepatic pyrites is in cubes and octahedra. 



Mcematite. Occurs in minute chocolate- coloured semiglobular 

 masses, made up of extremely minute crystals, also in an almost 

 continuous film, coating the calc-spar and other crystals with a 

 coppery sheen. In some cases the cavities containing minerals 

 have the haematite much more thickly deposited on the surface 



* I have just learned that this mine is now closed in consequence of the 

 expiration of the Lilleshall Company's lease. 



