THE CUBA REVIEW 21 



The ore is mined i>.\ band, mostly from open cuts, though shorl drills and tun- 

 nels have been run Into lenses of ore al the Ponupo, Cauto and Laura mines, and 

 a slope has been driven mi a thin tabular mass of ore between strata of limestone 

 dipping about 34° a I the Botsford. 



High-grade ore inaj be selected In mining the richer parts of the deposits, bul 

 most of the ore requires mechanical treatment, such as log washing and jigging, to 



free it of claj sand and other impurities, and, though it is ilms possible to in 



lain a shipping grade of ore, much is now lost in the tailings, Qol alone because the 

 concentrating apparatus used is simple and crude, but because the recover} of finely 

 divided manganese oxides is very difficull ami has nol yet been successfully accom- 

 plished. At one mine ore is cleaned by raking over a horizontal screen in a si renin 

 of water. Log washers were in operation at tour mines and were under construc- 

 tion al two others. Al one mine a system of washing, screening and jigging is em- 

 ployed. 



The daily product ion of manganese ore about the middle of March, 1918, in this 

 district was between 280 and 300 Ions a day. The output was curtailed later, in the 

 rainj season, which begins about the first of June, especially that from the smaller 

 mines, which are dependent on oxcart haulage, hut, the curtailment will be more 

 than offset by the increase in shipments alter the railroad from Cristo to the Ysobelita 

 mine has been opened. 



The approximate average composition of a large proportion of the ore now shipped 



is ;is follows : 



Manganese 38.885 Per rent. 



Silica Il^.loo •' " 



Phosphorus 084 " " 



Moisture 11.201 " 



The total output of manganese ore during 191S from the district near Santiago 

 will probably reach 110,000 tons, the greater part of which will contain between 36 

 and 45 per cent, of manganese, only a few thousand tons containing more than 4."» 

 per cent. 



The reserves of merchantable ore in this district are estimated at Gu0,000 to 

 700,000 long tons. 



DISTRICT SOUTH OF BAYAMO 



The manganese deposits that were examined in the district south of Bayamo 

 consist of the Manuel, the Costa group (Costa, Carbayon, Daniel, Oviedo, Vicente and 

 other claims), 18 to 23 miles by wagon road southwest of Bayamo; the Francisco and 

 Cadiz, 1". to 20 miles southeast of Bayamo; the Guisa, Llego and Charco Redondo, 

 7 or 8 miles southeast of Santa Rita, and the Adriana and San Antonio mines, 9 # to 10 

 miles south of Baire. Other deposits, farther southeast, are in what is known as 

 the Los Negros district. 



I. it tie nuning has been done in this district, and as most of the deposits, like 

 the Cuban manganese deposits generally, are richer near the surface than deeper, 

 it is still possible to produce high-grade ore here by selective mining. Deposits of 

 "milling" ore are also available and will undoubtedly be developed later if prices 

 remain favorable. 



The ores at the west end of the district, on the Manuel and Costa group, occur 

 in irregular masses of "jasper" or "bayate" associated with latite porphyry, and 

 those of the other properties farther east are associated chiefly with limestone and 

 comprise bedded and residual deposits. 



The development of the deposits south of Bayamo is handicapped by their re- 

 moteness from the railroad and by the lack of good wagon roads. The owners of 

 the Manuel mine and of the Costa group will soon make use of a road by way of 

 Bueycito to Julia, a station on the Cuba Railroad between Bayamo and Manzanillo, 



