Pacific Mining
pp. 70-71 · Read in the full issue
News
From Fiji.
Emperor Gold Mining Co. Ltd.
WITH its new large plant operating, Emperor Gold Mining Co., Ltd., at Tavua, Fiji, treat ed 11,426 tons of ore in the period Decem ber 26 to January 26 for a yield of 3665.6 oz. of bullion, estimated to contain 3,044 oz. of fine gold. This is the first clean-up with the plant, which has a designed capacity, including the original pilot plant, of 3,000 tons a week.
The yield represents a recovery of 5.33 dwt. fine gold a ton. The ore treated was of a head value of 6.8 dwt. a ton, and the gold content of the residues after treatment was 0.63 dwt. a ton.
Milling Derations, the management states, are now on the 12,000 tons a month schedule. Daily throughput for the last 10 days was 430 tons.
In the following table the latest production fig ures are compared with those of the two pre ceding four-weekly periods, when only the pilot plant was in operation:—
The wet season, the management of Loloma Gold Mines, Tavua, Fiji, states, has curtailed the handling of ore and reduced the running time.
The mill was shut down for six days during the holidays to convert the elevator housing from wood to steel. This is to effect an increase in throughput.
In 496V2 hours’ running, the mill crushed 1,663 tons of ore for a recovery of 1,790 fine oz. of gold and 591 fine oz. of silver. This represents a grade of 21.03 dwt. of gold a ton, compared with 25.53 dwt. in the preceding period. The management attributes the lower grade to mois ture in the hanging-wall causing extra dilution.
Residues assayed IV2 dwt. a ton. This compares with 3.4 dwt. in the tailings from the last per iod, and represents a considerable improvement on the result of the first clean-up in October when, because of treatment difficulties and plant absorption, the residues showed the high assay of 11.3 dwt. of gold a ton.
In the following table the result of the latest clean-up is compared with those of the two pre ceding periods:—
A report on development in the bottom (224 ft.) level states that the south drive off the main east crosscut at 60 ft. has been extended to 536 ft. The average assay value of the lode in the last 13 ft. of driving was 44 dwt. a ton over a width of 84 in. This indicates increases in both the width and the grade of the lode as driving has progressed.
Koroere Gold N.L.
Recent operations of Koroere Gold N.L., Tavua, Fiji, are reviewed in a progress report issued early in February.
Work on the Koroere Hill section has been concentrated on two points, No. 1 boundary shaft S. of the Emperor-Koroere boundary and No. 5 lower adit at the S. side of Koroere Hill. Both E. and W. crosscuts in No. 1 boundary shaft have been driven to a depth of 24 ft. to 24 ft.
An S. drive in a narrow band of stone was driven to 31 ft. S., but failed to disclose any definite lode body. While payable ore was loca ted, the average results did not indicate any quantity at this level. Work at this point has been stopped, and the labour transferred to pros pecting on an outcrop nearer the Emperor boun dary and also to two lode outcrops further W., known as the Brewster and Murchison. No. 5 lower adit at 36 ft. showed the first sign of hav ing intersected the old No. 5 lode, and at this point returned 0.8 dwt. a ton. This tunnel has
Nov. Dec. Jan.
Tons crushed 2,600 2,400 11,426 Head value, dwt 8.3 8.8 6.8 Yield, oz. (est.) ... 952 951 3.044 Dwt., a ton 7.3 8 5.33
Loloma (Fiji) Gold Mines N.L.
tNov. 24. Dec. 22.
Jan. 29.
Ore treated, tons . . 1,580 1,700 1,663 Gold, fine, oz 1,669 1,999 1,790 Dwt., a ton .. 21.13 23.53 21.03 Silver, fine, oz 757 755 591 Tailings assay, dwt. . 8.1 3.4 1.5 ton raw treatment 75 per cent, of period.
so far been driven by hand labour. A pipe line will be laid and machines installed. It is pro posed to drive this tunnel to at least 120 ft., which will take the face to the point where reasonably good values were returned from the original No. 5.
At the Cardigan mine the bulk of the work has been concentrated on the W. Cardigan, where a winze has been sunk in the E. crosscut 65 ft.
N. of No. 7 shaft and 18 ft. E. At 33 ft. the in crease in the volume of the water made further sinking difficult and expensive, and the work has been discontinued there for the time being.
While the bottom of the winze is still in lode formation, values tend to fade, and this, coupled with the difficulty of handling the water intake, made it advisable to discontinue. This work can be resumed after the wet season, when it is ex pected that further development of the winze will disclose a considerable tonnage of payable values. This winze is sunk in the centre of the lode channel, which is here 35 ft. in width, which returned good average values for the full width.
It will be necessary to sink a shaft from the surface over the location of the winze, a dis tance of 35 ft. in order to continue sinking, and, if necessary, driving and crosscutting at a lower level. Owing to the present wet season, it has been decided temporarily to stop this work and to make an immediate commencement with the sinking of the main shaft, Canadian lode, to the 200 ft. level. This shaft will be sunk in country rock, and it is not anticipated that there will be any difficulty with water.