152 GOLD JIIXIXG IX THE SOUTHERN APPALACHIANS.
Systematic work can only be pursued where the ore-bodies are large and continuous enough to warrant the establishment of a regular plant for mining, milling and reduction of the ores. The question of quantity means more than that of quality, so long as the former does not fall below a certain limit.
Among such may be classed the wide lenticular bodies of auriferous and pyritic slates, as at the Ilaile and Russell mines, and the persistent and continuous quartz-veins of sufficient width, such as at the Reimer and Capps mines. The more continuous and stronger ore-leads of the Dahlonega type may also be included here, such as at the Lock hart and the Franklin mines, which are at present being worked as deep mines, as well as those which have so far been worked by hydraulic-king, like the Hand, Singleton, Tindley, etc., mines.
In some localities smaller or irregular quartz-veins lying close together have been worked separately; it may prove feasible to mine these together as a body of low-grade ore, especially where the intervening and adjoining country-rock is to some degree auriferous, as at the Rocky River mine.
Such ores a.s are alluded to may be said to average between $3 and $7 per ton. There are exceptional cases of richer ore-bodies which have shown considerable continuity, as, for instance, at the Phoenix mine; but here, as is usual, the size of the vein and hence the quantity of the ore decreases proportionately with the improvement in the quality.
Almost without exception, a profitable extraction from Southern gold ores can only be attained by supplementing amalgamation with concentration of the sulphurets and by subsequent treatment of the latter. The practically universal adoption of the stamp-mill in the South verities, as in other gold-mining regions, its more general applicability for crushing compared with other machinery. The two types of stamp-mills more especially characteristic of the South, each having its own field of action, have been described on pages 111 and 119. The milling practice varies greatly, as might be expected from the extremely variable character of the ores.
All of the Southern ores contain at least a portion of their gold in the free state, and excepting where other ingredients offer serious obstacles, or where a smelting process is intended, concentration is best preceded by amalgamation, so as to obtain the free gold as soon as possible and not endanger it to loss in subsequent treatment. Especially where the sulphurets are coarse and the crushing is not fine, a preliminary sizing in hydraulic classifiers and spitzkastens. and the treatment of each size on a separate vanning machine, is advisable. There has been a tendency to overcrowd these machines in the South; a saving of original cost here is but poor economy. It would seldom be advisable
