SOME CONCLUSIONS CONCERNING GOLD MINING. 151
mines may be attributed to the pinching out of the ore-shoots outcropping at the surface or a diminution in the assay value of the ore. It is probable that the more expensive and difficult operations at such depths precluded the further search for other ore-bodies below the waterlevel. It must also be remembered that as early as 1810 at least partially successful attempts were made to work sulphurets.
In many of the mines, however, the ore-bodies were of low grade, though sometimes of large extent, and the small extraction of the free gold in the sulphuretted ores did not permit of a profitable continuation of the work. As in all mining regions, many other so-called plausible reasons are given for the abandonment of the mines, as, for instance, mismanagement, disputes among the owners, etc.
To determine the probable value of a mine an examination is of course absolutely necessary. A conclusive opinion is, however, in most cases impossible, even after the mine has been pumped out and examined, on account of the poor condition of the workings and the, at best, limited exposures of the ore-bodies. The prospective investor must, with few exceptions, bear the cost of the necessary exploratory development, which expenditure must be considered speculative. A great number of the properties are held at prohibitory figures, and arrangements for satisfactory examination under option or otherwise cannot be made, traditional merit and output being considered a sufficient proof of value by the owners.
In low-grade highly sulphuretted ore-bodies assays may give a fair indication of the value of the ore if the samples be fairly taken; but a test on a larger scale at one of the experimental chlorination plants,1 in cases where it is intended to subsequently adopt the chlorination process, would be much more conclusive.
On higher grade, free-milling ores, however, assays, even if taken with care, will be of little value; the results will, in fact, often be misleading. In such cases a mill-test is imperative, and it can generally be made either in the mill at the mine itself, at some neighboring mill, or at test mills especially operated for this purpose.2
The most feasible propositions in the South appear to be the working of the larger low-grade ore-bodies. Rich veins as a rule have been in pockets and of small extent, more suited to the operations of tributors or small landowners, with the help, perhaps, of the wooden stamp-mill. It is a well-known fact that ore-deposits of this uncertain character cannot be worked systematically by larger companies with an extensive plant, and must be left to the individual miner, whose persona] success pays his daily wages, and to whom an occasional strike is an inducement for continuous work.
1 Captain A. Tbies, Haile Mine, S. C, and Mecklenburg Iron Works, Charlotte. N. C.
2 Mecklenburg Iron Works, N. C, and the Salisbury Supply Co., Salisbury, N. C.
