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This occurs in the form of encrusting groups of minute and brilliant 

 dark-green crystals, generally lining cavities in the vein-stuff. 

 Usually it is associated with fibrous malachite, and with matter of 

 a more or less ochreous nature. It was discovered as a Cumber- 

 land mineral by Mr. Bryce M. Wright, who, as a native of Caldbeck 

 had abundant opportunities of making himself acquainted with the 

 minerals of Cumberland. Good specimens of Brochantite are in 

 each of our local museums. 



Without doubt the most beautiful of all the minerals obtained 

 from the Caldbeck Fells, or, perhaps, from any locality in the two 

 counties, is the Sulphato-Carbonate of Lead named Linarite, 

 from Linares, in Spain, whence some of the earliest-known speci- 

 mens of the mineral were obtained. In Cumberland it occurs 

 chiefly at Rowtin Gill and the adjoining mine of Red Gill. At 

 each locality it occurs in the form of thin, tabular crystals, usually 

 of small size, of a bright-vitreous lustre and of a brilliant blue 

 colour. It is found in association with Cerussite, Anglesite, and 

 other ores of lead, as well as of copper, in the fault-breccia of the 

 veins of that district. The mines have not been much worked of 

 late years, and Cumberland specimens are therefore now becoming 

 somewhat difficult to procure. But good specimens exist in the 

 museums at Carlisle, Keswick, and Penrith ; and there is a fine 

 series in the splendid collection of the British Museum. 



At Rowtin Gill and Red Gill Linarite and some of the minerals 

 generally associated with it are found chiefly in the outer parts of 

 the veins and near to the bottom of the valley. In the outer parts 

 of the same veins nearer to the fell-tops, the assemblage of minerals 

 is of a somewhat different kind, and includes species that, to say 

 the least of it, are decidedly rare at lower levels. The same 

 phenomena have been noticed elsewhere, and have been alluded 

 to on a former occasion. 



In connection with the extraordinary variety of decomposition- 

 products found along with Linarite in the Rowtin Gill area, there 

 are many facts that yet await a satisfactory explanation. It is just 

 possible that the peculiarly-complex and varied nature of the rocks 

 of that particular district may have had some share in contributing, 



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