156 Captain Franklin on the Diamond Mines of 



abundance of ironstone gravel and ferruginous matter strewed 

 over this part of the country necessarily produced in former 

 times, and no doubt still continues to produce, a great quanti- 

 ty of oxide of iron, which being washed away, and held in so- 

 lution by the minor streams, has been gradually deposited in 

 the channel of the Ranj river until it is now about ten feet 

 thick, and immediately below it are the beds of detla and sand- 

 stone, and the matrix as above-mentioned. This matrix does 

 not require to be broken, the clay is easily separated by wash- 

 ing, and the expence of working the mines is consequently les- 

 sened, but still they are not considered so certain in their re- 

 turn as those of the rocky matrix. 



Superficial Mines. — The chila, or superficial mines, are to 

 be found in every part of the diamond tract, excepting only a 

 circuit of about five miles from the cascade of the Bagin liver, 

 where it appears that denuding causes have swept them away 

 and all their contents into the glen of that river. Their ma- 

 trix is always red ironstone gravel in ferruginous sand or fer- 

 ruginous clay. Their geological position, with regard to the 

 descending series, appears to be remarkably well defined, for 

 they are actually to be found on the verge of two cascades, 

 having 400 feet of sandstone beneath them ; when this matrix 

 fills the fissures and interstices of the upper sandstone, angular 

 fragments of the rock are mixed with it, the corroding influ- 

 ence of the oxide of iron appearing to have detached them as 

 well as to have disintegrated and oxidated a portion of the 

 rock, so that the gravel and fragments are imbedded in sand 

 so highly ferruginous that it resembles the rust of iron ; but 

 when, on the other hand, it is imbedded in ferruginous clay, 

 it contains no fragments of sandstone, and is constantly found 

 overlying slaty marl or sandstone, or detla, as in the instances 

 above-mentioned ; with regard to the ascending series, its geo- 

 logical position seems also to be well defined, for, if the two 

 strata of red ironstone gravel and kankar occur together, as 

 they do at Sakeriya, it always underlies the calcareous bed, 

 and their line of separation is distinct, so that, when they hap- 

 pen to mingle as at Bangla, the matrix acquires a new name, 

 and is then called hadda. 



These mines rarely exceed five or six feet in depth, and are 



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