MINING

Hokitika Guardian, 13 July 1931, Page 2

MINING

OKARITO FIVE MILE BEACH DREDGING CO. The report of the directors of the 'Okarito Five Mile Beach Gold Dredging Company, Limited, for the half-year ended March 31 states: — The second annual report and balance sheet was, issued to shareholders at the end of November, 1930, and the second annual general meeting of the company was held on December, 19, 1930. At this meeting a full report was given to .shareholders on the progress made up to that time with the construction of the dredge an'd the recommendations of the directors regarding .additional capital were approved and adopted. In January, 1931, shareholders were circularised regarding the debenture stock issue of £SOOO. The issue was over subscribed by .nearly £3OOO, and the debenture stock was taken up entirely by shareholders in the company. It has since been fully paid up. t Since the annual meeting, the construction of the dredge has progressed steadily, but on account of unforseen delays and difficulties the dredge was not able to commence operations by the end of April as had been estimated, and it was not until June 10, 1931, that the dredge Was actually completed and had had a trial run, A full acount of the dredge is contained in the sattached report of Messrs Wheeler, bee and Mitaon who , visited the claim just after . the dredge had started. In view of their report, ; it is unnecessary for further details ;to be repeated .here regarding the dredge and the claim. Sluicing operations were carried on until April 20|, and up to this date' a further twenty-four ounces of gold were obtained,, additional to the total of 211 ounces 2dwts. won during the half-year ended March 31, 1931, and shown in the sluicing account for the half-year. It was necessary by the end of April to discontinue sluicing in order to connect. the pipe line with the dredge.

' Shareholders . are' already , aware that the first' wash-up from the dredge-was 40 ounces for broken week which contained only seventy-two hours’ dredging time. The second week’s, result was 120 ounces sdwts. for 126 hours’ dredging, .while the return for last week was 100 ounces 6dwts. for 112 hours. The average working expenses and .overhead are •estimated to total approximately. 25 ounces per week, so that the dredging operations already carried out have been highly profitable. ; : - ,v'The report on a visit of inspection by the chairman of directors and others to the claim, ,is as follows: . At the request of the Board of Directors we visited the company’s claim. at the Okarito Five Mile Beach, and now stibmit, for the shareholder's’ itlfortnaTidn) ; ' lh6 fofiowihf^eport,— The dredge started operations on three shifts on Tuesday, June 16, and we arrived at the claim at naan on Baturday, June 20, Wo spent six days there, md had ample opportunity of, making a thorough inspection of the claim and .of.the dredge under working conditions. - Transport:-—The problem of transport ceased with ~the completion of the dredge; although there will always be stores;and a certain amount of material to be taken from Okarito to the claim. At the present- time the beach route is impassable for cartage. In fact it is dif- , ficult travelling .on . foot even, at low tide. The road over the hill to the Three Mile Creek is ifi fair order. The steep grades, however, .will' always make this route difficult for . transport. The County Council is easing the steep descent to the Three Mile Creek-and intends to build a bridge over the creek, The completion of this work will greatly improve the access to the claim and will make the crossing of the Three Mile Creek possible at all times. The , Dredge.—This is a splendid job and in every way suited to the wurk ahead of it. The pontoons are large, but no larger • than necessary for the machinery and the spread of gold-saving boxes and tables. .They are substantial and well-built, and will prove a good foundation to the machinery, and this .will do much to reduce the wear and tear to a minimum. Nothing but the best grade of timber has been used in the construction of the- pontoons and super-structure,-.and we feel sure that they will outlast the life of the claim. The lay-out of the machinery is good, and proper • attention has been paid to convenience of working and to accessibility. The work of installation has been carried out in a substantial manner *0 'As tit stand up to the work required of the dredge. As shareholders are aware, most of .the machinery came from a dredge on the iSaltwate'r Beach.. Certain parts were badly corroded, but these have nil been either repaired or replaced by new material, and the machinery now is as good as new. Some of the buckets the Saltwater dredge were much corroded, but those that could not be repaired satisfactorily were discarded and replaced by new ones. The . machine -y all through is in such a condition as to ensure steady and efficient wording of .the dredge.

Power. The power is obtained from a direct coupled pelton wheel T.ue water ii conveyed to the dredge iron the ma.n pipe line by a line of 9-inch pipes. A ■simple but efficient arrangement of boats and swivels allows great freedom to the dredge while working or manoeuvring. The pelton wheel is producing ample power for all purposes. ■More power can be obtained from it -f required, but it-, is not anticipated that this necessity will arise; The main pipe line is capable of delivering 7 cusecs and at present the dredg?? is only using 3.6 cusecs. Fresh water for the boxes and tables is being pumped from the dredge paddock by means of a hydraulic pump which delivers 12 cubic feet of

water per second. This is proving ample for all requirements. The level of the water in Lake , Alpine and .the overflow from the lake showed that there need be no misgivings as to water supply. The housing of the dredge provides good light during the day time and an electric dynamo, driven by a small pelton wheel, supplies a satisfactory light at night time.

Gold slaving.—The gold saving arrangement is the most important and interesting feature of the dredge. Careful tests of the tailings and close obsevation of the boxes and tables satisfied us that our engineer’s promises to provide an efficient method of treating the material to extract the gold had been fully carried out. We believe the dredge can treat up to 80 cubic yards per hour and effect a very high percentage of gold recovery. The total gold saving. surface is about 120 Q square feet. The buckets discharge into' a sluice box about 60 feet long. This is provided with cocoanut matting with plates punched with 5-16 inch holes suspended above the matting. All material that cannot pass through the plates is conveyed by the sluice box some distance beyond the stern of the dredge and dis- j charged into the paddock. The fine material, after passing through the plates on to the matting, is drawn off from the sluice box at intervals and passed 1 over a series of tables covered with cocoaiiut matting. After leaving the. tables, the material is caught in boxes provided with cocoaiiut matting and ripples, and conveyed beyond the stern of the dredge and discharged into the paddock. -Every convenience ia provided to reduce loss of time in lifting and cleaning mats. Temporary arrangements have been provided for "streaming down ” but a convenient permanent “streaming-idowp” table will shortly be installed. At no time did we observe any silting up on the mats, and the absence of gold in the tailings showed that- the mats were catching the gold. Up to the present the tailings have been easily dealt with, but, so far no high ground has been worked. A tailings elevator is to be installed and ready in case of necessity. It is proposed to work the claim from the present sife the dredge with a face half the width of the claim on the lagoon side until the northern boundary is reached. The dredge will then work south on the seaward half of the clami back to the starting point. From then on -it will work the full width of the claim until the southern boundary is reached. The dredge is now employed in opening up the working face, It will probably take four weeks to open up the full width.

Labour.—The dredge-master has a good staff under him, and the dredge was being well handled. As their experience of the nature of the ground increases, so will the throughput of material increase.

General.—During the first week’s run, the dredge operated for seventy-two hours and gave a return of forty ounces of gold. For the second week the dredging time was 126 hours and the gold recovered' 120 ounces sdwts. tt Is the board's, intention to publish in the Press all weekly returns as soon as they,'come to hand, The week’s work will be faken from 8 a.m. on Saturday to 8 a.m. the following Saturday. The ounces won for that period, along with the number of dredging hours, will be published. In conclusion we wish to express our satisfaction with our visit to the claim and our belief that the company’s future is a bright one, and that steady and satisfactory returns will be received.