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LANCEFIELD.-THE BATTERIES.

who, coming from Lancefield, in Victoria, baptised the new find after that town. The reef does not outcrop on the surface, but by lucky chance the prospectors met with some gold-bearing

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'floaters" and following up these indications, they discovered the reef, which was about fifteen feet in width. The party then set to work, but, after toiling for some months and finding the ore of lower grade than in those days was considered profitable, two of them abandoned their interest and proceeded elsewhere. The work of the prospectors was, at the outset, surrounded with many difficulties, and at one time they were on the point of throwing up their lease. In 1898 the owners of a 10-head battery at Hawk's Nest decided to crush for the public, and the consequence was that the prospectors were enabled to reap an immediate return for their labours. These crushings brought the district into some prominence, and amongst those they attracted to the locality was Mr. T. W. Horton, the manager of the Malcolm Proprietary, at Murrin Murrin. Other leases were taken up. Mr. Horton secured a 10-head battery, which had been lying idle for two years about ten miles distant, and this was brought and erected on the Lancefield, and Mr. C. F. Strauss, who had been engineer in charge of the Mount Malcolm Proprietary, joined the syndicate. In November, 1898, the battery

was placed in position, and Mr. Strauss has since then had the entire management of the property. During the progress of the erection of the plant, the necessary preparatory work on the mine was being carried out, and, fortunately,

an adequate water supply was obtained. January, 1899, saw the completion of the erection work, and the commencement of active crushing operations. In February the first clean up took place from a crushing of 140 tons, the result being an average of about 8 dwt. to the ton. From that time the mill has been kept continuously going, and to the end of May, 1901, the total quantity of ore treated was 23,208 tons, from which 6,644 oz. of gold was obtained, being an average of nearly 6 dwt. per ton. Owing to the extreme fineness of the gold in the ore, the value of the tailings is very high, as shown by cyanide treatment for 11,612 tons leached up to the end of May gave 5,317 oz. 11 dwt., the average being a little over 9 dwt. to the ton. It was not, however, until December, 1899, that a start was made to cyanide the tailings, which had been accumulating from the commencement of crushing. The results at the time were of such a highly satisfactory character, that the plant was increased to its present capacity of 1,100 tons per month. The total extraction, taking the amalgamation and cyanide results together, has been 15 dwt. per ton, but it is satisfactory to learn that indications point to even better results in the near future, when it is anticipated that the average will be

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LANCEFIELD.-CHANGING SHIFT.

a few pennyweights better. The conditions are reported to be so favourable to economical working that it is conjectured even 8 dwt. per ton would show an appreciable profit. The mine is worked from a main underlay shaft, sunk to a depth of 200 ft. This shaft is only 100 ft. from the battery, and at the commencement of operations the advantages of this contiguity were very important. At a depth of 40 ft. in this shaft a level was driven north and south along the main lode for a distance of 140 ft., and from this the battery was kept going all the time at a moderate cost. At 90 ft. a main level has been driven south for a distance of 140 ft., the ore being of good value throughout. At this point the reef

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level has been extended north a distance of 502 ft., making the total length of driving at the 90 ft. level 642 ft., the reef averaging about 18 ft. in width the entire distance, with ore of average value still showing in the face. Here the main development work is being done, and the quartz broken out goes direct to the mill. Two-thirds of the stone crushed comes from this face, the remainder being obtained from stopes above this level. Throughout the entire 642 ft. of driving from face to face, the reef varies in width from 10 ft. to 25 ft., the average being 18 ft., and the stone in value varies from 8 or 9 dwt. to 18 dwt.

per ton. The higher-grade stone is confined to a length of about 150 ft. in the neighbourhood of the shaft. The reef has been exposed on the surface north of the workings by costeens in two or three places. In one of the costeens the reef is quite 30 ft. wide, showing payable ore, and it is not considered probable that there will be any depreciation in the

value of the stone in the north face for

a further length of 700 ft. The reef throughout is of free milling stone, with occasional bands of schist, varying in thickness from a few inches up to five feet. The gold contents are consistently regular, even the schist carrying a fair proportion. The gold is extremely fine, and only in rare cases is the gold visible at all in the stone. The 200 ft. level has but recently been reached, and the main object of the management was to connect with No. 1 winze south, for ventila

tion purposes. This was done by a small drive of 22 ft., along the reef, which has only been cut through in one place, and there it is of the total width of 14 ft.

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In the course of sinking, at a distance of 35 ft. vertically, water was first met with, but no considerable increase was encountered in sinking to 90 ft. At that level, however, in driving along the reef the supply rapidly increased, and now it is estimated to be 60,000 gallons per day. The water is of excellent quality, and has little perceptible effect on the boilers. The original baitery of 10 head of stampers was made at the Sandycroft foundry, and is an efficient one in all respects, as is demonstrated by the fact that it has crushed over 1,000 tons per month. Besides this, another 10-head Fraser and Chalmers mill has been erected, making twenty

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head of stampers at work, and a new Fraser and Chalmers tubular boiler has also been added to the mine's equip ment. From a rock-breaker the ore is elevated by an inclined tram-road to storage bins, and delivered thence to the battery by Challenge automatic orefeeders.

Owing to the mine being situated on a flat, it is necessary to elevate all the tailings, and this is accomplished by means of a pneumatic elevator. The small compressor which supplies air for this elevator requires very little power to drive it, therefore entailing but little expenditure in up-keep, while, as proof of efficiency, no stoppages have yet been recorded through its failure. To provide the motive power there is a large single-cylinder horizontal engine and two Cornish boilers, manufactured by Davy, Paxman and Co. As at present constituted, this engine is capable of driving the 20 head of stampers, but when another cylinder has been added to it, its design providing for such an addition, it would be easily capable of driving 50 head of stampers. The cyanide plant is constructed of iron, with twelve leaching vats, capable of treating 22 tons each. Prior to its erection, there had been a gradual accumulation of tailings, but these are being worked off, the cyanide capacity being greater than is required to treat tailings from a tenhead battery. The ore makes a large percentage of slimes, and, notwithstanding that it is crushed through a coarse

mesh (700 holes to the square inch), it was found necessary to instal a slimes plant.

There has been excellent judgment exercised in the management of this mine. The cost of all the improvements, additions to plant, and developments have been paid for out of the earnings of the mine, and the history of the concern is certainly creditable to all who have had a responsible position in connection with it. Not three years ago the whole of the subscribed capital of the company was £750. It is certainly a remarkable circumstance that this modest amount has been all that has been necessary for the opening up of the property. Those few fortunate individuals who joined in Mr. Horton's venture have not been called upon to add a single penny to their original investment. For a conjoined outlay of £750 they have not only secured a valuable property, but from its own earnings the mine has been thoroughly equipped, the improvements comprising a 20-head mill, a cyanide plant, a slimes plant, and extensive development work. Over and above this, the directorate have been able to declare a dividend of 4d. per share monthly for the past twelve months. All this has been accomplished from stone which, by battery and cyanide treatment, has only averaged 15 dwt. to the ton. When it is taken into consideration that, in the future, there will be neither plant nor improvements to be paid for, there can be no question that a stone equal to 8 dwt. per ton will be profitably worked.

CRAIGGIEMORE.

Ma

This property was discovered in 1896 by Messrs. Duncan Rose, Alex. Fraser, and Alex. McPhail. Eventually, Dr. Laver became actively interested in the property, with the result that he proceeded to England, and floated it into a company, in which he and the original prospectors still retain a large interest. The area of the mine is 100 acres. chinery was erected on it in 1899, but so rapid has been the development, and so satisfactory the results, that recently the plant received important addition 3, and now the Craiggiemore is not only thoroughly well equipped, but has obtained the reputation of being one of the most economically worked mines in Western Australia. This result has been attained despite the fact that it has not had the advantage of railway communication, and has consequently had to surmount the difficulties of heavy freights and working expenses. The plant has hitherto consisted of a twenty-head battery, capable of crushing over 2,000 tons per month, together with a complete cyanide plant capable of treating 1,500 tons per month. In July, 1901, however, an additional ten head of stamps were erected. Development work on an extensive scale is in progress. The main shaft has been sunk to a depth of 250 ft. At the 100 ft. level, 500 ft. have been driven along the line of reef, and at the 200 ft. level 320 ft. have been driven. An excellent water supply has been obtained, equal to 100,000 gallons a day, which of itself is of incalculable benefit.

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