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with a lustre closely approaching that of the diamond in brilliancy. 

 The same remark applies also to Driggith Mine, and various 

 other mines in the Caldbeck Fells ; to Greenside Mines at the head 

 of Ullswater ; and to various mines in the Alston district, as well 

 as in other localities not so generally well-known. Beautiful 

 groups from Braithwaite Mines adorn both the National Collec- 

 tions, as well as most private collections of any extent. 



It is not a little remarkable that Cerussite should be so commonly 

 associated with Galena, while Anglesite, the Plumbic Sulphate, 

 should be very local in its distribution. On theoretical grounds, 

 Anglesite ought to be found wherever Galena is undergoing con- 

 version into the Carbonate ; as the Sulphide is supposed, as the 

 initial step in its alteration, to combine with a further proportion 

 of Oxygen, and thus to pass first into the Sulphate before going 

 over to the condition of Carbonate. The fact that Anglesite and 

 Cerussite occur side by side as decomposition-products of one and 

 the same crystal of Galena, as happens in the Caldbeck Fells for 

 example, while in other districts the Cerussite occurs alone, and 

 that, too, without shewing any signs of having passed through the 

 preliminary stage of Anglesite, would seem to indicate that the 

 formation of Cerussite from Galena is due frequently to conversion 

 direct from the Sulphide. Were the case otherwise, Anglesite, 

 seeing that it is nearly as stable a compound as the other lead 

 salt, ought to be of at least equally common occurrence as a 

 decomposition-product, which is certainly not the case in the lead 

 mines of the North-West of England. 



Cerussite is very valuable as an ore of lead ; but in Cumberland 

 and Westmorland it rarely occurs in sufficient quantity to render 

 it of much importance in a commercial aspect. 



It is, perhaps, worthy of remark that the " old man'" (as metal 

 miners in the North call the former workers of mines, as well as 

 the results of those Avorkers' labours,) seems often to have been 

 unaware of the value of this mineral as an ore of lead, and to have 

 rejected it along with the refuse as worthless " deads." In the 

 case of mines where this has happened, modern improvements in 

 the dressing of ores have rendered it worth while to sort over and 



