Bendigo General History - Department of Planning and Community ...

At the White Hills a considerable amount of money and labour have been invested in sluicing
operations, and fair returns have been obtained, which the sluicers hope to increase by crushing the
cement in connection with the washdirt. With a more abundant supply of water, many more miners
would be engaged in this branch of mining. The quantity of water sold for mining purposes during
the past quarter was - For crushing, puddling, &c., 12,934,000 gallons; for sluicing, 101,352,000
gallons: total, 116,286,000 gallons. The following information respecting the United Pyrites
Company’s Chlorination and Amalgamation Works, Sandhurst, has been kindly supplied by C.W.
Chapman, Esq., secretary to the company. These works up to about twelve months ago were simply
for washing, grinding, and amalgamating with mercury, and for which there were three reverberatory
furnaces, two of J. Edward’s patent grinding machines, and sixteen arastras and separators, driven by
a 20 horse-power engine, which also drove a plunger pump. The works were capable of treating 45
tons per week, and gave employment to eighteen men and boys. Seven of these arastras and
separators were taken out, and a large addition to the building made for a chlorination plant, the rest
of the old plant remaining the same, so as to treat the sulphides by either process, to suit the
requirements of customers. The chlorination plant consists of four vats, to contain four tons each -
one vat for three tons, and one for two tons; a considerable number of earthenware gas generators,
heated by loose steam, and a large number of earthenware vessels to hold the auriferous solution and
solution of sulphate of iron. Attached to the chlorination establishment is room for storage, a drying
oven, and three melting furnaces. The chlorination plant is capable of treating forty-five tons per
week, and the amalgamating or old process about thirty tons per week. Attached to the establishment
is a four-stamp battery for crushing quartz for filter beds or any other hard material, and the water
supply is obtained from three large dams belonging to the same proprietary. The works employ
twenty-one men and boys, two men and drays carting pyrites, and three men and drays carting
firewood. A very large quantity of sulphuric, nitric, and hydrochloric acid, mercury, soda, meal,
peroxide of manganese, sulphate of iron, firewood, coke, charcoal, crucibles, borax, nitre, sulphide of
iron, pitch, tar, lead pipe, indiarubber sheet and pipe, and glass and pottery ware, is used up. The raw
pyrites as it is brought from the crushing machines is charged into the reverberatory furnaces, and
roasted until all the volatile matters are driven off and the sulphates converted into oxides; it is then
ground, moistened, and placed in the vats, which are hermetically closed; the chlorine gas is then
turned on for a sufficient time to attach the gold and convert it into chloride. The covers are then
lifted, and the vat filled with cold water, which, after having dissolved the auriferous chloride, is run
through lead pipes into earthenware vessels. In these the gold is precipitated from the mother liquor
by sulphate of iron; the waste liquor is syphoned off, and the cement gold caught on filter papers
placed within earthenware funnels, dried in the oven, and smelted in Hessian crucibles in a wind
furnace. The gold produced in this way realises from £4 2s 6d to £4 3s 0d per ounce. The value of
the plant, machinery, dams, stores, &c., is about £5,000, and about from £500 to £700 more is
generally employed in purchasing pyrites. The sulphides from St Arnaud, Burke’s Flat, and other
places which resist ordinary processes, yield their gold readily to this method. Pyrites tailings from
the amalgamation process when re-worked by chlorination always yield a profit. These works have
never been stopped since starting except for overhaul at Christmas. Railway freight is a heavy
charge upon this industry, especially in the case of acids, on which, although the rate has been
reduced by one-half, it is still very heavy - £2 19s per ton for full truck loads. 1
Sept 1879: During the past three months a greater quantity of quartz has been crushed, but the average yield is
not so good as that of last quarter. Very good yields have been obtained from quartz obtained at from
800 to 1,000 feet in depth. New finds in old mines on the principal lines of reef have been numerous,
and some of them have proved valuable. It is generally believed that, were the mines thoroughly
prospected by means of crosscuts driven by the aid of speedy rock-borers, the finding of payable
reefs would be of more frequent occurrence. A few rock-borers are in use here, at a saving of from
20 to 25 per cent in cost of crosscutting and sinking. Mining prospects have improved during the
past quarter, but unfortunately a strike of miners is immediately expected, which will probably
seriously affect all concerned in mining. About three weeks since the tributers in the St Mungo
Company’s lease struck a very rich leader at 60 feet from the surface, the first ton of which yielded
256 oz of gold. The stone continues exceedingly rich. About the same time a nugget of gold
weighing 38 oz was found in the Whipstick 6 inches below the surface. At the present time it is
rumoured that a rich quartz reef has been discovered about 4-1/2 miles east of the forest ranger’s
residence in the Kamarooka and Egerton State forest. The quantity of water sold during the quarter
for mining purposes was - For crushing, &c., 15,680,000 gallons; for sluicing, 86,660,000 gallons;
total 102,340,000 gallons. 2
Sept 1879: Garden Gully United, Garden Gully Reef - New and extensive winding machinery being erected over
No. 3 shaft. 3
1 Mining Surveyors’ Reports, June 1879
2 Mining Surveyors’ Reports, September 1879
3 Mining Surveyors’ Reports, March 1879