DEPOSITS OF NORTH WALES. 365 



" There was no carbonate of lime, some fluoride of calcium, 

 alumina, and oxide of iron. 



" The darker-coloured contained more graphite, and were richer in 

 phosphate of lime than the lighter- coloured specimens." 



2. Penygarnedd Mine. I am enabled, through the courtesy of 

 the manager, to say generally that the bulk of the deposit here 

 averages 46 per cent, of phosphate of lime. 



3. Berwyn Mine. Through the kindness of Messrs. F. C. Hills & 

 Co., of Deptford, I am able to give the following full analyses of the 

 deposit at this mine, which I have developed from its commencement 

 in February 1872. 



A. Analysis of concretionary nodules by Mr. D. Hesketh Kichards, 

 of Oswestry. 



Moisture and organic matter 4-200 



Sand ./. 22-600 



Tribasic phosphate of lime 64-165 



Oxide of iron and alumina 6-890 



Other constituents not determined .... 2-145 



100-000 



Another analysis 4)£ similar concretions gave 61*44 phosphate of 

 lime. 



B. Analyses of two consignments from the bulk of the deposit. 



I. II. 



Loss on burning 6-77 3-06 



Phosphoric acid* 22-54 20-92 



Lime 31-08 30-13 



Oxide of iron and carbonic acid 19-12 22-88 



Insoluble matters 20-49 23*01 



100-00 300-00 



C. Five other analyses of the bulk of the deposit, made by Messrs. 

 Hills, gave an average of 46-85 phosphate of lime. There was also 

 in all the samples about % per cent, of copper. 



Llanfyllin. Analysis made of the phosphorite bed near this town 

 gives a range of from 20 to 30 per cent, of phosphate of lime. 



Dinas Mowddwy and Llan-y-Mowddwy. Two samples from the 

 deposit north-west of these villages gave the following proportions of 

 sulphur and phosphate of lime. 



Phosphate of lime 2-90 1-72 



Sulphur 34-38 34-20 



The rest is made up of sand, iron, and alumina. 



* Equal to tribasic phosphate of lime 49-207 4567. 



