The PFS which is the subject of a separate announcement made today, demonstrates the technical and financial viability of constructing a simple, low-strip ratio, open-cut mining operation and processing facility producing spodumene concentrate. The positive PFS demonstrates the opportunity to create substantial long-term sustainable shareholder value at a manageable capital cost.
The positive PFS is considered sufficient to determine, in accordance with the JORC Code 2012, that a subset of the Measured and Indicated Mineral Resource (please see ASX announcement "Authier Lithium Project JORC Resource Updated", 11 December 2017) be classified as Ore Reserves - see Table 1 in link below.
The PFS demonstrates that a viable mining and processing operation, and the infrastructure to support this, are available to develop the project. The PFS takes into account all the modifying factors considered material to the development of the project and statement of Ore Reserves. The inputs into the economic and financial analysis were based on realistic assumptions of technical, engineering, operating and economic factors. The capital and operating cost estimates were obtained from reputable consulting groups at the appropriate level of confidence for the PFS.
JORC Mineral Resource Estimate
The Authier project has been subject to more than 27,000 metres of drilling. Between 2010 and 2012, Glen Eagle completed 8,990 metres of diamond drilling in 69 diamond drill holes of which 7,959 metres were drilled on the Authier deposit; 609 meters (5 DDH) were drilled on the Northwest and 422 metres on the south-southwest of the Property.
Sayona Mining has completed two phases of drilling including 49 drill holes for 8,084 metres, including 12 drill holes for 639 metres in Authier North pegmatite. All the holes completed by Sayona have used standard diamond drill holes (DDH), HQ or NQ core diameter size, using a standard tube and bit. The drilling programs have been subject to very robust QA/QC procedures.
An independent JORC Mineral Resource (2012) estimate for the Authier pegmatite deposit and Authier North pegmatite deposit is reported as per Table 2 (see ASX release, Authier JORC Mineral Resource Upgraded, 17 December 2017).
The Mineral Resource estimates for the Authier and Authier North pegmatites are based on reported intercepts calculated using arithmetic averages, no top-cut, and a 0.45% Li2O cutoff grade. The estimation was based on an Inverse Distance Squared interpolation using Micromine software.
The parent block dimensions used were 3 metres x 3 metres x 3 metres with sub-blocks of 1.5 metres x 1.5 metres x 1.5 metres in accordance with the drill spacing and pegmatite body geometry. Three dimensional mineralized wireframes were used to domain the Li2O data using a 0.45 % Li2O cut-off for mineralised domain limits. Sample data was composited to 1.0m down hole lengths. Specific oriented ellipsoids search were used for grade interpolation at each pegmatite deposit.
The Measured Mineral Resource was defined within areas of close spaced diamond drilling of less than 35 metres by 35 metres, and where the continuity and predictability of the spodumene bearing pegmatite was high. The Indicated Mineral Resource was assigned to areas where drill hole spacing was less than 60 metres by 60 metres. The Inferred Mineral Resource was assigned to areas where drill hole spacing was greater than 60 metres by 60 metres generally in the edges of the known mineralisation mostly in the down-dip extensions beyond the last drill holes in each section.
JORC Ore Reserve Estimate
The revised ore reserve was derived from Sayona updated Pre-Feasibility Study on its 100% owned Authier lithium Project (see ASX release, Authier Optimised Pre-Feasibility Study Demonstrates Excellent Returns - Definitive Feasibility Study Underway, 17 December 2017). The revised Ore Reserve Estimate totals 11.66Mt at 1.03% Li2O (see Table 5 in link below).
This revised Ore Reserve estimate is in line with Industry best practice standards and reported according to the guidelines set by the JORC Code, 2012 Edition. Sayona had previously released an Ore Reserve estimate completed by SGS Geostat (see ASX release, Authier PFS, 22 February 2017).
A site visit was attended by the CP, Mr Jonathan Gagne, in June 2017. During this site visit the CP was able to meet with site representative, view the proposed infrastructure sites, the proposed pit location relative to the natural terrain, the surrounding general infrastructure and regional setting.
The resource model used as the basis for this Ore Reserves update was also compiled by Dr. Gustavo Delendatti, based on the latest available drilling information.
The Mineral Resource estimates for the Authier and Authier North pegmatites are based on reported intercepts calculated using arithmetic averages, no top-cut, and a 0.45% Li2O cutoff grade. The estimation was based on an Inverse Distance Squared interpolation using Micromine software. The parent block dimensions used were 3 metres x 3 metres x 3 metres with sub-blocks of 1.5 metres x 1.5 metres x 1.5 metres in accordance with the drill spacing and pegmatite body geometry. Three dimensional mineralized wireframes were used to domain the Li2O data using a 0.45 % Li2O cut-off for mineralised domain limits. Sample data was composited to 1.0m down hole lengths. Specific oriented ellipsoids search were used for grade interpolation at each pegmatite deposit. The Mineral Resources reported are inclusive of the Ore Reserves reported here.
The Ore Reserves are reported at a 0.45% Li2O cut-off, in line with the reporting of the Mineral Resources. This cut-off which is above the theoretical economic cut-off has been selected to increase the feed grade to the process facility.
Sayona carried out open pit optimisation utilising Whittle4X(R) software on the Measure and Indicated Resource material. Slope design criteria, mining dilution, ore loss and processing recoveries were applied in the pit optimisation process together with mining, processing, transport and sales cost estimates, and revenue projections to form the basis for pit designs and subsequent mining and processing schedules.
The outcome of the optimization was used to perform the detailed pit design. The design indicates a pit of ~1,00 metres in length (east-west), an average of 600 metres width (north-south) and down to a final pit depth of 200 metres. The proposed open-pit is presented by the Figures in link below.
To view the full release with tables and figures, please visit:
About Sayona Mining Ltd
Sayona Mining Limited (ASX:SYA) (OTCMKTS:DMNXF) is an Australian-based, ASX-listed (SYA) company focused on sourcing and developing the raw materials required to construct lithium-ion batteries for use in the rapidly growing new and green technology sectors. Sayona’s primary objective is developing the Authier lithium project in Quebec, Canada. Authier is an advanced, near term development project, construction forecast to commence in the second half of 2018 and first production in late 2019. Please visit us as at www.sayonamining.com.au
Sayona Mining Ltd