HARRISON COUNTY. 141 



the ore banks. Picked specimens, which would represent a much higher 

 grade of ore, might easily be obtained from the same localities, but samples 

 which could be considered as of fairly representative character only were 

 taken. 



These analyses were made of the ore as brought from the banks, without 

 any previous calcination or driving off water or carbon dioxide, and although 

 they show a fairly good grade of ore, the methods of washing, calcining, and 

 desulphurizing this class of ores, as practiced in their ordinary workings, 

 would show them to carry a higher percentage of metallic iron than the 

 analyses given. 



In these analyses it is also assumed that under the present methods of 

 working this class of ores, and the existing facilities in the shape of fuel, flux, 

 transportation, etc., as well as the great quantities of higher grade iron ores 

 being put upon the market, ores carrying less than forty per cent of metallic 

 iron can not be profitably worked. 



In the case of the conglomerate ores none of the samples analyzed show a 

 sufficient value to be worked for their metallic iron. The best sample of this 

 class of ores (No. 795) gives an analysis of: 



Silica , 25 90 



Ferric oxide 62. 31 



Metallic iron 43 . 65 



One hundred parts iron contain 0.71 of phosphorus. 



The only means of working the conglomerate ores will be by crushing and 

 concentrating, and until some cheap and efficient method of doing so can be 

 found these ores may, although showing over forty per cent of metallic iron, 

 be considered as non-productive ores. 



The impurities found in association with the laminated and geode or 

 nodular concretionary ores are generally of a very trifling character, and are 

 mostly sulphur and phosphorus in small proportions. The proportions of 

 sulphur are very low, ranging from a mere trace to 0.12 per cent among the 

 laminated ores and increasing slightly in the geode or nodular ores, reaching 

 0.17 per cent in No. 748. These ores can readily be desulphurized by any 

 of the ordinary methods of washing and roasting or calcining now in practice 

 in the preparation of such ores for the furnace. 



The percentages of phosphorus existing in the ores are very small, and 

 some of them, such as Nos. 749, 804, and 808 among the laminated ores, 

 and Nos. 751 and 811 among the nodular concretionary ores, contain so 

 small proportions of this impurity as to entitle them to be ranked as Besse- 

 mer ores. 



Of the geode or nodular concretionary ores Nos. 751 and 811 belong to 

 the Bessemer class of ores, as shown by analyses. 



