Discovery of Diamonds in the Uralian Mountains. 267 

 Wished, is it not possible also to err by holding, that the econo- 

 my of nature must have been the same at every period of the 

 earth's existence, however strongly all appearances may pro- 

 claim a difference ? — Whewell. 



On the Discovery of Diamonds in the Uralian Mountains. 



Diamonds in the Brazils are found in those tracts that afford 

 also gold and platina. Some years ago, platina was found along 

 with gold at Nishnei-Tura, in Uralian Russia ; a circumstance 

 which naturally led to the suspicion, that the diamond might 

 also be a native of that quarter of the old world. The late dis- 

 covery of the diamond in Russia has shewn the accuracy of this 

 conjecture. This gem was discovered in the Urals in a ravine 

 named Adolphskoi ; which, besides the diamond, affords also 

 platina and gold. The district has many characters in common 

 with the diamond districts in Brazil ; their comparison will pro- 

 bably enable us to answer the question, as to the original repo- 

 sitory of the most precious of all the gems. In M. Moritz von 

 Engelhardt's very interesting account of the repository of the 

 Uralian diamonds, which he had the goodness to send to us, 

 there are many important details, some of which we shall now 

 present to our readers. 



Black dolomite alternates in the ravine or valley of Adolph- 

 skoi, with silver-white talc-slate, with black limestone, contain- 

 ing embedded scales of talc, and with white limestone, with em- 

 bedded scales of talc, grains of quartz, and small balls and cubes 

 of brown iron-ore. The limestone bed, when the embedded 

 quartz increases in quantity, forms the transition into itacolu- 

 mite. 



From which of the above mentioned rocks are the diamonds 

 of the Valley of Adolphskoi derived ? Not from the talc-slate 

 and limestone, because the alluvium, from their disintegration, 

 contains none ; nor from the itacolumite (flexible quartz) and 

 the gold veins, the quartz of which seems little fitted for origi- 

 nating pel feet crystals, such as the garnet dodecahedron of the 

 diamond ; therefore, probably, they occur in the black dolomite, 

 or some other rock which has been removed by weathering or 



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