OF ARKANSAS. 39 



and stunted trees of oak and pine which grow upon it, would lead one to 

 suspect. 



The cavernous limestone of LafTerty creek, is traversed by veins of dif- 

 ferent varieties of manganese ore. The most interesting locality is on the 

 west branch of Lafferty creek, two miles above its mouth. Here, there 

 appear to be regular veins with well-defined walls, traversing the caver- 

 nous limestone, containing the manganese ores. The course of the 

 main vein, with probably some subordinate cross courses, runs N. N. W. 

 andS. S. E. 



I measured the space between the faces of the walls of the veins at 

 different places where excavations had been made for the ore, and found 

 them to vary from 14 feet inches to 8£ feet. These ran down through 

 an encrinital bed of limestone, which is elevated about 200 feet above the 

 mouth of Lafferty creek. 



The masses of manganese ore taken out of these crevices vary in weight 

 from a few ounces to 30 or 40 pounds. From the most productive part of 

 the vein a man could raise from 300 to 400 pounds per day. 



Judging from the specimens taken out, and which lay strewed in abund- 

 ant heaps on the hill-side near the crevices, there appear to be two varie- 

 ties of manganese ore obtained at these mines, in the depth to which the 

 superficial and partial mining operations have yet been carried; one a 

 compact, close-textured ore of a dark steel-grey color, and a hardness of 

 about 5£ to 6, having the physical aspect of that variety of compact 

 manganese ore described in works on mineralogy under the name of 

 " psilomelane," composed of mixtures of the oxides of manganese, with, 

 usually, some baryta and potash; but from a partial qualitative examina- 

 tion made of this Lafferty creek manganese ore, it appears to contain but 

 a trace of baryta. 



The other variety is more crystalline in its structure, brighter in its 

 lustre, and of a lighter steel-grey color; but in hardness, streak, and color 

 of the powdered mineral (blackish brown), differs but little from the 

 former more compact variety.* 



W hether these two varieties differ only from some admixture of acci- 

 dental ingredients, or have a decidedly different atomic proportion of 

 manganese and oygen, will appear when the quantitative chemical analy- 

 ses are completed and recorded in the Chemical Report; then the ques- 

 tions bearing on the commercial value of these ores will be decided. 



So far as I can learn, the company who own these mineral lands on 

 Lafferty creek, in Independence county, and who made an attempt to 



*The analysis of these ores, recorded in the Chemical Report, proves these two varieties to be 

 essentially of the same constitution, the first containing, however, 3 or 4 more per cent of silica. 



