NEW METHOD OF CURING COPPER PLATES.

Westport Times, Volume III, Issue 444, 2 January 1869, Page 2 (Supplement)

NEW METHOD OF CURING COPPER PLATES.

Some days ago we referred to an improved method of coating copper plates with quicksilver, rendering them immediately capable of catching the gold effectually, and entirely removing the verdigris which has hitherto embarrassed the miner in using tables coated with quicksilver. The Charleston Herald has been furnished with the following particulars relative to the subject : —Reckoning 1 grain of gold to cure one oz. of copper on a plate 4ft. by 2ft., we have 2oz. Bdwl. of gold practically lost to the miner. To this we must add at least as much more, lost by its passing over previous to the plate being cured.; the value of the gold which thus eludes the miner's, grasp, equalls about £lB 10s for each plate in use; and according to the present method of allowing plates to cure themselves, it will take from two to four weeks of labor and gold lost before the miner can reap any reward for his labor. Here again we have an equivalent or *y tor eash man employed on the claim, so that our figures stand thus : —Value of gold deposited on plates before cure, £9 5s ; value of gold lost by transit, £9 ss; total, £lB 10s. Now eight plates each £lB 10s, will equal £148; four men each two weeks at £4 10s, per man, £36; cost of eight plates cured, £lB4. This will give an average of £23 for each plate. The plates being cured, the miner commences to reap his reward as soon as he begins to work, for the gold no longer passes over but is arrested on the plate, and can be scraped whenever it is deemed desirable. The advantages of using cured plates are manifest and need no further comment, and experience has proved that plates can be completely cured in the course of a few hours. There is now to be seen on the tables of the Southern Cross Company, on Darkie's Terrace, a plate cured by this process, and any plate, no matter what size, can now be effectually cured in Charleston at a few hours' notice, and or considerably less than one half the fresent cost.