AI assistant
EQ RESOURCES LIMITED — Capital/Financing Update 2011
Mar 22, 2011
64867_rns_2011-03-22_b8312899-bf2a-4dca-a54b-da5e3bfb7023.pdf
Capital/Financing Update
Open in viewerOpens in your device viewer
==> picture [91 x 98] intentionally omitted <==
EXCELLENT RESULTS FROM XRAY ORE SORTER TEST WORK ON THE MINERALISED WASTE STOCK PILES AT MT. CARBINE
Summary:
-
The Ore Sorter test work on the bulk samples of the low grade stockpiles at Mt Carbine has been completed on schedule and in accordance with the business plan.
-
Very significant pre-concentration of WO3 is achieved by using an X-ray ore sorter, and as a result of these tests, re-treating the low grade stockpiles is now a viable prospect.
-
The Mineralised Waste Stockpile with a feed grade to the ore sorter of 0.09%WO3 showed an 88% mass rejection at a grade of 0.01% WO3, and an “Accepts” grade of 0.7% WO3 with a WO3 recovery of 90% to the “Accepts”.
-
The historical Optical Ore Sorter Rejects Stockpile with a feed grade to the ore sorter of 0.05% WO3 showed a 74% mass rejection at a grade of 0.008% WO3, and an “Accepts” grade of 0.18% WO3 with a WO3 recovery of 89% to the “Accepts”.
-
Preliminary ore sorting testwork on the remnants of the ROM stockpile shows 67% mass rejection at a grade of 0.01% WO3, with a feed grade to the ore sorter of 0.12% WO3 and an “Accepts” grade of 0.33% WO3 with a WO3 recovery of 93% to the “Accepts”.
Overview of Ore Sorting
Ore sorting is a physical beneficiation technique commonly used to separate barren rock fragments from mineralised rock fragments extracted from a mine. The low-grade ore is bulk mined at low mining cost, and by rejecting the barren rock, ore sorting greatly reduces the amount of ore that has to be further processed to extract the valuable minerals. Hence, the size of the required processing plant is greatly reduced, which has the effect of reducing the capital required to build the processing plant and also reduces operating costs. This low cost, efficient mining and processing system also acts to place the mine using this system in a very competitive position if metal prices fall.
Ore Sorting was used very successfully at Mt Carbine between 1974 and 1986 and the mine historically was in the lowest quartile of cost of production during that period, but the ore sorters were designed to sort on the basis of the colour of rock fragments, or in later years, on the fluorescence of tungsten mineral on the surface of rock fragments.
However, technology has improved in the last 25 years and one of the latest developments has seen X-Rays being used to distinguish between mineralised and barren rocks.
The ore sorter that has now been used at Mt. Carbine, during these trials, was leased from Applied Sorting Technologies. This Australian based company specialises in X-Ray ore sorting and the unit used by Icon Resources is a second generation X-Ray ore sorter which has higher throughputs than previous models and a more powerful X-Ray source with more sensitive detectors. In this model sorter, the X-rays penetrate through the rock fragments and thus can identify minerals that are hidden within the rock fragment as well as those on the fragment surface.
==> picture [91 x 98] intentionally omitted <==
==> picture [427 x 284] intentionally omitted <==
Second Generation Applied Sorting Technologies X-Ray Ore Sorter being used at Mt Carbine December 2010.
==> picture [425 x 258] intentionally omitted <==
Mineralised Waste Stockpile Locations at the Mt Carbine Operations
==> picture [91 x 98] intentionally omitted <==
Stockpile Bulk Sampling
The nature and distribution of the tungsten mineralisation in the Mt Carbine ore and mineralised waste stockpiles presents a sampling problem, essentially only solved by taking and testing large samples. The same method of sampling was used for the three stockpile areas. Eight costeans were cut in to the stockpiles at equal intervals on the benches. It was determined that creating costeans (trenches) as a method of obtaining the samples would increase the accuracy of the sampling process. The „trenches‟ are at least 50 metre in length and 10 metre deep and with the majority of sampling taking place on the lower benches as the lower benches are proportionally larger than the top benches.
Each trench produced some large rocks and “fines”. These were separated and stockpiled on either side of the trench, sampled according to recognised practice (“coned and quartered”), and reconstituted proportionally based on the volume of each sample produced from each trench.
The quartered samples from each trench were combined and coned and quartered to produce two stockpiles, with a total weight of approximately 2,000 tonnes, comprising a fines stockpile and a stockpile of large rocks that required rock breaking before being presented to the crusher.
After rock breaking, the oversize and fines were recombined, crushed and placed on pads ready for feeding to the ore sorter.
==> picture [425 x 279] intentionally omitted <==
Bulk Sampling of Low Grade Mineralised Stockpiles
==> picture [91 x 98] intentionally omitted <==
Ore Sorter Operation
The ore sorter was run on 12 hour day shifts with samples meticulously taken every hour from the Feed, “Accepts” and “Rejects” conveyor belts. These samples from the individual streams were combined to produce composite samples for further analysis and assaying.
At the end of each 12 hour day the weight of the “Accepts” and “Rejects” stockpiles were taken so that detailed mass balancing could be performed. The resultant daily stockpiles were stored separately.
==> picture [265 x 397] intentionally omitted <==
Ore Sorter “Accepts” Conveyor
==> picture [91 x 98] intentionally omitted <==
Ore Sorter Results
| Mineralised Waste Stockpile |
Optical Ore Sorter Rejects |
ROM Stockpile (Preliminary Testwork) |
|
|---|---|---|---|
| FeedGrade(WO3 %) | 0.09 | 0.05 | 0.12 |
| Rejects Grade(WO3%) | 0.01 | 0.008 | 0.01 |
| AcceptsGrade(WO3%) | 0.7 | 0.18 | 0.33 |
| Upgrade Ratio | 7.7:1 | 3.6 :1 | 2.8 :1 |
| WO3Recovery | 90% | 89% | 93% |
| Mass Rejection | 88% | 74% | 67% |
Implications for future production
These results are highly significant because in the mineralised waste stockpile alone there is a historical estimate of 12 million tonnes of mineralised rock. The economics of re-treating this stockpile is enhanced by the fact that the rock has already been mined and only needs crushing before being fed to the ore sorters. Icon is very encouraged by the results of the ore sorter trials, and is now embarking on a plan to commence production at Mt Carbine by re-treatment of the tailings (ASX announcement 7[th] January 2011) followed by retreatment of the mineralised waste stockpiles. If this plan proves to be feasible the re-treatment of the mineralised stockpiles will provide feed for planned production rates for at least 6 years.
Production from the hard rock resource is still anticipated, but Icon will be able to gain a significant role in the tungsten supply chain before hard rock mining is commenced. During this time further drilling of the ore body is planned, with the intention of increasing the hard rock resource, thus providing a wider range of mining options to be assessed before mining and processing the hard rock resource.
For further information regarding this announcement, contact:
Ian Sheffield-Parker Managing Director
Icon Resources Ltd Ph: +61 (0) 409 989 960 +61 (0) 7 4078 6290 Email: [email protected]
23[rd] March 2011
Further information relating to Icon and its projects can be found on the Company‟s website at www.iconresources.com.au.