Getting Gold: A Gold-Mining Handbook for Practical MenJohnson, J. C. F. (Joseph Colin Francis)
History
Getting Gold: A Gold-Mining Handbook for Practical Men
Johnson, J. C. F. (Joseph Colin Francis)
Gold mines and mining
Some twenty-five years since I also was engaged on the construction of a
dry amalgamator in which sublimated mercury was passed from a retort
through the descending gangue in a vertical cylinder, the material
falling therefrom through an aperture into a revolving settler, the
object being to save water on mines in dry country. The model, about
quarter size, was completed, when my attention was called to an American
invention, in which the same result was stated to be attained more
effectively by blowing the mercury spray through the triturated material
by means of a steam jet. I had already encountered a difficulty, since
found so obstructive by experimentalists in the same direction, that
is, the getting of the mercury back into its liquid metallic form. This
difficulty can be largely obviated by my own device of using a very weak
solution of sulphuric acid (it can hardly be too weak) and adding a
small quantity of zinc to the mercury. It is perfectly marvellous how
some samples of mercury “sickened” or “floured” by bad treatment, may be
brought back to the bright, clean, easy flowing metal by a judicious use
of these inexpensive materials.
Thus it will probably be found practicable to crush dry and amalgamate
semi-dry by passing the material in the form of a thin pasty mass to a
settler, as in the old South American arrastra, and, by slowly stirring,
recover the mercury, and with it the bulk of the gold.
The following is from the _Australian Mining Standard_, and was headed
“Amalgamation Without Overflow”:
“Recent experiments at the Ballarat School of Mines have proved
that a deliverance from difficulties is at hand from an unexpected
quarter. The despised Chilian mill and Wheeler pan, discarded at
many mines, will solve the problem, but the keynote of success is
amalgamation without overflow. Dispense with the overflow and the
gold is saved.
“Two typical mines--the Great Mercury Proprietary Gold Mine,
of Kuaotunu, N.Z., the other, the Pambula, N.S.W.--have lately
been conducting a series of experiments with the object of saving
their fine gold in an economical manner. The last and best trials
made by these companies were at the Ballarat School of Mines, where
amalgamation without overflow was put to a crucial test, in each
case with the gratifying result that ninety-six per cent. of the
precious metal was secured. What this means to the Great Mercury
Mine, for instance, can easily be imagined when it is understood
that notwithstanding all the latest gold-saving adjuncts during the
last six months 1260 tons of ore, worth £4. 17_s._ 10-2/3_d._ a ton,
have been put through for a saving of £1 9_s._ 1-2/3_d._ only; or
in other words over two-thirds of the gold has gone to waste (for
the time being) in the tailings, and in the tailings at the present
moment lie the dividends that should have cheered shareholders’
hearts.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Elsewhere in the archive
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account