Extracting Gold from Pyrites.

Thames Star, Volume XVII, Issue 5286, 29 December 1885, Page 2

Extracting Gold from Pyrites.

It is no exaggeration to say that in these colonies there are millions of torn of pyrites containing from 3ozs to 20ozi of gold per ton besides a quantity of baser metals, but which have as yet proved of no value in consequence of the difficulty of treatment. To overcome this difficulty, a number of experiments were made by Mrs Parnell, a lady of considerable experience in metallurgy and chemistry, and the result was the introduction of a new process known and patented as the Par. Nell process for the extraction of base and precious metals from pyrites.; In thia process no salt or chemical!'of any description .are used. The soluble sulphates are formed solely in and from the ores, and all the bi-products of oxides are saved. The solvbles and sulphites are then extracted from .the ores by means of boiling, the gold and a portion of the silver being left per* feotly free and ready for amalgamation or smelting. The first public trial of thia process was made at the Austral Foundry, Pyrmont, Sydney, this month in the presence of jajjujmber ofj scientific and commercial gentlemen, when three lots of ores were examined in different stagea. One of these parcels consisted of I4owt Sjrom the Black Jack Mine; Ravenswood (Queensland), and the yield obtained waa 301bs of copper and 4ogs of gold. As the cost of treatment is set down at £2 per ton for simple pyrites and £3 per;ton for refractory pyrites, there should be a large margin for profit in ores of far poorer quality than those yet tried. As a test that the minerals were in perfect solution it may be mentioned that those present dipped their penknives into the material and found, on withdrawing them, that the blades .were coated with copper. '■ *"| (' * V