Penrose.] PHOSPHATES OF NORTH WALES. 83 
Forbesii, Cycloceras arcuatum, G. Sonax, Orthocerata, Illcenus Davisii, 
and other forms. 
The phosphate bed of North Wales was discovered by a miner in 18G3, 
in a raviue near Cwmgwynen, 5 miles from the town of Llanfyllin. 
At first the nature and value of the bed were unknown, but finally a 
specimen was sent to Dr. A. Volcker, who analyzed it and made known 
its importance. Several mines have since been started at Cwmgwyueu, 
Penygarnedd, Berwyn, Llanfyllin, and other places, but none of them 
has been successful and at present no Welsh phosphate is mined. 
The reasons for this want of success were the distance of the mines from 
any railroad or navigable river, the low percentage of phosphoric acid 
(see analyses), and the depressed state of the phosphate market. More- 
over, the bed is expensive to work, as regular mining operations are 
necessary to win the phosphate; it also often contains considerable 
iron, which causes superphosphate made from it to have a sticky con- 
sistency. 
Analyses of North Wales rock iriwsphates. 
\I and II. Analyses of two specimens from Cwrugwynen, by Volcker (Quart. Jour. Geol. Soc. Lon- 
don, 1875).] 
I. II. 
Phosphate of lime 64.16 48.50 
"There was no carbonate of lime, some fluoride of calcium, alumina, and oxide of 
iron. 
"The darker-colored contained more graphite and were richer in phosphate of 
lime than the lighter-colored specimens." 
fill. Analyses of nodule from Berwyn mine, North Wales, by D. H. Richards (ibid., vol. 31, pp 
364, 365).] 
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 of a similar nodule gave 61. 44 per cent, phosphate of lime. 
[IV and V. Analyses of Berwyn mine phosphate, North Wales, by F. C. Hills and Co. (ibid., p. 365).] 
IV. V. 
Loss on burning 6.77 3.06 
Phosphoric acid (1) 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 
Total...: 100.00 100.00 
(1) Equal to tribasic phosphate of lime 49.207 45.67 
Five other analyses of the bulk of the deposit, made by Messrs. Hills, gave an aver- 
age of 46.85 per cent, phosphate of lime. There was also in all the samples about 
one-half per cent, of copper. Analyses of phosphate from near Llanfyllin, North 
Wales, gave Messrs. Hills "a range of from 20 to 30 per cent, of phosphate of lime." 
(Quart. Jour. Geol. Soc. London, .1875, vol. 31, p. 365.) 
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