204 



is worth of remark that stains of Malachite may now and then be 

 traced to the decomposition of Pyrites, which frequently includes 

 a notable percentage of Copper Sulphide in its composition. 

 Another point worth calling attention to is the marked association 

 of the Green Carbonate with the veins of silicified limestone, 

 already referred to under Quartz. 



In the Lake district the mineral is of common occurrence, 

 though not in quantities sufficient to render it of much commercial 

 importance. 



The beautiful mammilated Malachite, familiar to most persons 

 as being employed for ornamental purposes, comes from foreign 

 localities ; as, though the mineral does occasionally occur in such 

 forms in our district, the masses are rarely of either sufficient 

 purity, or size, to be available for that purpose. On the other 

 hand, while Malachite in the form of crystals is by no means 

 common elsewhere, many excellent examples have been obtained 

 from the renowned locality of the Caldbeck Fells. The crystals 

 referred to are found chiefly at Rowtin Gill, Haygill-, and Mexico 

 Mines ; and Mr. Bryce Wright gives, as other localities, Carrock 

 End, and Dale Head, and also Stavely, near Windermere. The 

 Rowtin Gill specimens occur in the form of groups of very slender 

 acicular prisms, with a silky adamantine lustre and an emerald- 

 green colour, which shoot inwards towards the centre of some of 

 the cavities in the vein-stuff. In every case Malachite seems to be 

 clearly due to the decomposition of other minerals containing 

 Copper. 



Malachite is sometimes used as a pigment, under the name of 

 Mountain Green ; but it is not very permanent. 



The other hydrated Copper Carbonate, Azurite, or Chessylite, 

 occurs under much the same conditions as the last-named species, 

 and at many of the same localities. It is, however, of much less 

 common occurrence. Occasionally this mineral is found well 

 crystallized, and its rich deep-blue tint renders it one of the most 

 beautiful of the minerals occurring in our district. 



(To be concluded in No. IX.) 



