Nordic Mines AB (publ): Encouraging Assay Results
Post# of 301275
On 26 th September Nordic Mines ('The Company') announced the successful completion of a 70-ton sorting test at the Bjorkdal mine, Sweden. 25 tons of material was sent to two laboratories in Finland for sample preparation and assay.
We have now received assay results from the first batches of the Bjorkdal sorting test samples. Further assay results will be received in January.
We are very encouraged by the results to date. It is evident that optical sorting systems have the potential to transform the economics at the Laiva mine. However, there is room for improvement, both in sorter settings and washing for cleaner rock surfaces to facilitate quartz detection.
Whilst the forecast upgrades to 1.33 g/t are close to our best expectation, it is clear that further threshold optimization work needs to be carried out on the volcanics, the second of the ore types. Over aggressive threshold settings carried out on the volcanics during the tests, resulted in losses of gold in the waste, which with further adjustment of settings, we believe will be reduced. The settings used allowed mainly larger quartz particles to be sorted as ore and many of the smaller quartz particles were reported as waste. By lowering the threshold settings for quartz in the ore type volcanics, more quartz including gold reports to the sorted ore stream.
Because optical sorting systems are in themselves a secondary strip, the exercise of going forward becomes a fine balance between increasing gold grade together with management of the waste fraction. Optimisation programs will continue even during the commercial phase. Table 1 presents the average result from the assays received. Further threshold tests are planned for the New Year.
Table 1. Average results from sorting test (including some preliminary assays)
| Ore Type | Pit | Sorted rock size mm | Sorter feed gold grad g/t | Mass-% Ore after sorting | Mass-% Waste after sorting | Gold upgrade of ore after sorting | Gold down- grade of waste after sorting | Recovery of gold in the sorting plant | Number of Samples |
| Quartz Diorite | North | 50-100 | 0,73 | 30 % | 70 % | 130 % | -50 % | 65 % | 4 |
| Volcanics | South | 50-100 | 0,85 | 17 % | 83 % | 166 % | -28 % | 40 % | 5 |
| One sample is outside expected gold grade range and not included in the average. | |||||||||
| Quartz Diorite | South | 50-100 | 2,29 | 36 % | 64 % | 113 % | -63 % | 77 % | 1 |
It is important to note that the sorted ore will make up less than 50 % of the feed to the plant. The majority of the ore feed to the process plant are particles finer than the sorted rock being below 50 mm in size. The fines derive partly from blasting, when the ore is mined, and partly from two crushing steps before the ore is further treated. The gold grade in this finer material is much higher than in the material that goes to the sorter because it contains more gold bearing quartz. Quartz is brittle and breaks down easily when blasted and crushed so that quartz and hence gold will accumulate more readily in finer particles. Also reporting to the feed is grinding media which by definition is comprised of coarser rock pieces measuring up to 200 mm. These have a lower gold grade than the material going to the sorter. Together these three materials, sorted ore, fine particles and grinding media, make up the final feed to the plant.
Andrew Malim, Head of Laiva Mine Development comments We are pleased to report that based on an average - run - of - mine grade of 0,95 g/t, we estimate an upgrade of 40% for the assayed sorted quartz diorite ore combined with fines and grinding media which would be reporting to the mill. Further assay results are due in January 2017. The use of optical sorting during our commercial production phase is expected to lower our cutoff grade and hence upgrade our mineable reserves. This will allow a bulk mining approach which will transform our base case economics and make Laiva a profitable mine at current gold prices.
Upgrading results are most affected by thresholds and the size of the ore fractions. Hence, for reasons explained in this Release, ongoing optimisation of the programs will be necessary prior to and during operations from which I believe further grade improvements are still achievable.
CEO's Commentary The recent sorting tests at Bjorkdal confirm our belief that the use of optical sorting used in tandem with the existing new AG mill will significantly enhance the grade and quality of our mill feed and provide the basis of a profitable restart of mining operations at Laiva once refinanced. We would like to thank the dedication of our staff and the advice and input of our partners at Outotec. More testwork on the volcanics will take place in the coming months and we believe that further grade improvements are achievable with practice and experience. We look forward to keeping shareholders updated with our progress
For additional information, please contact : D. Saradhi Rajan, CEO: +44 207 993 5261 (switchboard) or Rune Nordström, Head of Corporate Communications and Investor Relations: rune.nordstrom@nordicmines.com , +46 70 602 65 20
For more information about Nordic Mines, please visit; www.nordicmines.com.
This information is Nordic Mines AB (publ) obliged to make public pursuant to the EU Market Abuse Regulation, the Swedish Securities Market Act and Financial Instruments Trading Act. The information was submitted for publication, through the agency of the contact person set out above, at 1.30 pm GMT on 21 December 2016.
Nordic Mines is a Nordic mining and exploration company. The Laiva mine in Finland produced gold between 2011 and 2014. The deposit is among the largest in the Nordic region. Nordic Mines is a member of SveMin and applies its reporting regulations for public mining and exploration companies. The Nordic Mines share has been admitted for trading on Nasdaq Stockholm's Small Cap list. For further information, see www.nordicmines.com.
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