FOREIGN MINING REGIONS. 377 



Marie aux-Mines : argentiferous galenite (affording 1-1000 of silver), 

 with pyrornorphites, tetrahedrite, antimonial sulphuret of silver, na- 

 tive silver, arsenical cobalt, native arsenic, and pyrite, occasionally 

 auriferous ; affording silver and lead ; rocks : argillaceous schist, sye- 

 nyte, and porphyry. 



20. In France there are also the mining districts of the Alps, Au- 

 vergne or the Plateau of Central France, Brittany, and the Pyrenees, 

 but none are very productive, except in iron ores. Brittany resembles 

 Cornwall, and formerly yielded some tin and copper. The valley of 

 Oisans in the Alps, at Allemont, contains argentiferous galenite, arseni- 

 cal cobalt and nickel, gray copper, native mercury, and other ores, in 

 talcose, micaceous and syenytic schists, hut they are not now explored. 

 The region of Central France is worked at this time only at Pont- 

 Gibaud, in the department of Puy-de-Dome, and at Vialas and Ville- 

 fort in the Gard. The former is a region of schistose and granite 

 rocks, intersected by porphyry, affording some copper, antimony, lead, 

 and silver ; the latter of gneiss, affording lead and silver, from argen- 

 tiferous galena. The French Pyrenees are worked at the present time 

 only for iron. 



21. In England there are two great metalliferous districts : 



A. On the southwest, in Cornwall, and the adjoining county of De- 

 vonshire : pyritous copper and various other copper ores, tin ores, 

 galenite, with some bismuth, cobalt, nickel and antimony ores ; afford- 

 ing principally copper, tin, and lead ; rocks : granite, gneiss, micaceous 

 and argillaceous schist, elvanyte. 



B. On the north, in Cumberland, the adjoining parts of Durham, 

 with Yorkshire and Derbyshire, just south : galenite, and other lead 

 ores, blende, copper ores, calamine and smithsonite (the zinc ores es- 

 pecially at Alstonmoor in Cumberland, and Castleton and Matlock, in 

 Derbyshire^, affording some zinc, and three-fifths of the lead of Great 

 Britain, and some copper ; rock : Carboniferous limestone. 



C. There is also a vein of calamine, blende, and galenite, in the 

 same limestone at Holywell, in Flintshire, on the north of Wales ; 

 another of calamine at Mendip Hills, in Southern England, south of 

 the Bristol Channel, in Somersetshire, occurring in magncsian lime- 

 stone ; mines of copper on the Isle of Anglesey, in North Wales, in 

 Westmoreland and the adjacent parts of Cumberland and Lancashire, 

 in the southwest of Scotland, the Isle of Man, and at Ecton in Stafford- 

 shire, &c. 



22. In Spain there are mines — 



A. On the south, in the mountains near the Mediterranean coast, 

 in New Grenada, and east to Carthagena, in Murcia ; also in New 

 Grenada, in the Sierra Nevada, or the mountains of Alpuj arras, the 

 Sierra Almagrera, the Sierra de Gador, just back of Almeria, and at 

 Almazarron near Carthagena : galenite, which is argentiferous at the 

 Sierra Almagrera and at Almazarron, affording full 1 per cent, of 

 silver ; rock : limestone, associated with schist and crystalline rocks. 



B. The vicinity of the range of mountains running westward from 

 Alcaraz (to the district of LaMancha), to Portugal. 1. On the south, 

 near the centre of the province of Jaen, at Linares, latitude 38° 5', 

 longitude 3° 40': galenite, cerussite, cuprite, malachite, in granite and 

 schists ; affording lead and copper. 2. In La Mancha, at Alcaraz, 

 northeast of Linares, latitude 38° 45' : calamine affording abundantly 



