Cardinal Upgrades Indicated Mineral Resource to 6.5Moz
As a result of an additional 15,684m of HQ diamond drilling within 35 holes since the last Mineral Resource estimate in September 2017, the infill drilling program has been successful in delivering a substantial conversion of the Inferred category ounces into the Indicated Mineral Resource category which is now at 6.5Moz of Indicated Mineral Resources and 0.5Moz of Inferred Mineral Resources.
- 6.5Moz of gold contained in 180Mt at 1.13g/t Au at a cut-off of 0.5g/t Au within the Indicated Mineral Resource category
- 0.5Moz of gold contained in 13Mt at 1.2g/t Au at a cut-off of 0.5g/t Au within the Inferred Mineral Resource category
- Remains open along strike and down dip
- Maiden Ore Reserve estimate and Pre-Feasibility Study due mid-2018
Cardinal's Chief Executive Officer / Managing Director, Archie Koimtsidis stated:
"We are extremely pleased that our intensive infill drilling campaign has significantly upgraded our confidence in the Namdini deposit with an overall lift in Indicated Mineral Resources from 4.3Moz to 6.5Moz. Further to this, we are confident that Namdini can continue to grow with more drilling given it remains open both along strike and down dip, with mineralisation intersected down to 650 vertical metres, and still open.
"This upgrade to the Mineral Resource ismore than a 50% increase in the Indicated category from the estimate published in the September 2017 NI 43-101 technical report and supports a long mine life as demonstrated by the results of the recently announced Preliminary Economic Assessment.
"With the majority of the Indicated Mineral Resource continuous from surface to an approximate vertical depth of 400m, we anticipate a conversion of Mineral Resources to Ore Reserves within a simple, single, large-scale open pit, with a very low strip ratio of 1.2 to 1 over the life of mine as the preferred mining method.
"The higher-grade areas of the deposit, close to surface, will be targeted within the Stage 1 pit in the early years of production, as the recent results of our PEA study indicate, this pit will be the area most likely to repay capital investment soonest. The Stage 1 pit will see approximately 400,000oz to 900,000oz produced over three to four years at an average head grade of approximately 1.3 to 1.5 g/t Au based upon the PEA results and the throughput size selected."
MINERAL RESOURCE UPGRADE
This Mineral Resource update incorporates the results from the latest infill drilling program which was completed in Q4 2017 totalling approximately 15,684m in 35 drill holes. The primary aim of the drilling program was to infill the deposit within the conceptual pit to focus on converting the remaining Inferred Mineral Resource to the Indicated category. This drill program also incorporated grade control, pit geotechnical, hydrogeology and tailings infrastructure drilling. With all of these programs completed, we will be able to produce an Ore Reserve estimation as part of the Pre-Feasibility study which is currently scheduled to be completed in mid-2018.
Table 1 (see link below) highlights the Mineral Resource estimation reported at a series of cut-off grades. Currently the 0.5 g/t Au cut-off grade approximates an operational parameter that the Company believes to be applicable. This is in accordance with the guidelines of Reasonable Prospects for Eventual Economic Extraction ("RPEEE") per the Canadian Institute of Mining, Metallurgy and Petroleum "CIM Definition Standards for Mineral Resources and Mineral Reserves" (CIM, 2014) and the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code 2012). Refer to Sections 1, 2 and 3 of the JORC Code 2012 Edition Table 1 (see link below) criteria in Appendix 1. The effective date of this Mineral Resource estimate is 5 March 2018.
All figures in Table 1 (see link below) have been rounded to reflect the relative accuracy of the estimates.
MINERAL RESOURCE ESTIMATE PARAMETERS
The following information summarizes key parameters relating to the Mineral Resource estimation:
- Geological and structural modelling: Logging, interpretation and modelling were undertaken by Cardinal Resources' technical staff and specialist structural consultants Orefind Pty Ltd, (Davis and Cowan, 2016-2018) updated the three-dimensional model of key lithologies, structures and weathering zones.
- Survey Control: A detailed topographic survey was completed using Lidar technology, a remote sensing method used to examine the surface of the Earth. Drill hole collars were surveyed using differential GPS (DGPS), with down hole surveys taken at 30m intervals using electronic multishot and gyroscopic equipment.
- Bulk density data: Bulk densities are routinely measured as part of exploration data acquisition protocols. The bulk density database for the Mineral Resource estimate comprised 8,132 measurements. Statistical analysis was undertaken on the bulk density data and a matrix of bulk densities were applied based on lithology and weathering zone. The large majority of the Namdini deposit is fresh rock. Bulk densities vary from 1.80 tonnes per cubic metre (t/m3) for strongly weathered rock to 2.73 t/m3 (for granite) and 2.82-2.83 t/m3 for metavolcanics, diorite and metasediments.
- Grade Estimation: MPR Geological Consultants Pty Ltd ("MPR") (QP/CP Mr. Nicolas Johnson) estimated recoverable Mineral Resources for Namdini using Multiple Indicator Kriging ("MIK") with block support adjustment, a method that has been demonstrated to provide reliable estimates of recoverable open pit resources in gold deposits of diverse geological styles. The mineralized domain used for the current study was interpreted by MPR and Cardinal geologists on the basis of two metre down-hole composited gold grades and captures zones of continuous mineralization with composite grades of greater than nominally 0.1g/t Au. The domain trends north-northeast over 1.2km and dips approximately 60o to the west with an average horizontal width of approximately 350 m. The Mineral Resource can reasonably be expected to provide appropriately reliable estimates of potential mining outcomes at the assumed selectivity, without application of additional mining dilution or mining recovery factors. Validation of the MIK model was undertaken visually, statistically and comparatively, with an alternate Ordinary Kriged model estimate (OK). All checks were found to be within estimation accuracy.
The Mineral Resource classification also considered the quality of the data collected (geology, survey and assaying data), the density of data, the confidence in the geological models and mineralization model and grade estimation quality.
- Variance Adjustment: MPR's resource estimates include a variance adjustment to give estimates of recoverable resources at various gold cut off grades. The variance adjustments were applied using the direct lognormal method. The variance adjustment factors reflect comparatively large scale, open pit mining consistent with Cardinal's perception of potential mining scenarios. The variance adjustment factors were estimated from the variogram model for gold grades assuming mining selectivity of 5m by 10m by 2.5m (across strike, strike, vertical) with high quality grade control sampling on an 8 by 12 by 1.25m pattern.
Figure 1 in link below, is a perspective view of the mineralization wireframe constructed to encapsulate the data used for the block model generation. The conceptual Starter and Life of Mine pits from the recent Preliminary Economic Assessment ("PEA") results, are displayed.
Figure 2 in link below, shows the distribution of Indicated and Inferred Mineral Resources through a longitudinal slice of the block model.
Figure 3 in link below, shows the grade distribution and continuity through a longitudinal slice of the block model. The higher-grade areas towards the northern part of the resource, close to surface, will be targeted in the early years of production within the starter pit.
Figure 4 in link below, shows the distribution of Indicated and Inferred resources through a typical crosssectional slice of the block model.
Figure 5 in link below, shows the grade distribution and continuity through a cross sectional slice of the block model.
The Mineral Resource is prepared in accordance with both the Canadian Institute of Mining, Metallurgy and Petroleum "CIM Definition Standards for Mineral Resources and Mineral Reserves" (CIM, 2014) and the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code 2012). Refer to Sections 1, 2 and 3 of the JORC Code 2012 Edition Table 1 (see link below) criteria in Appendix 1 (see link below).
A technical report in support of the mineral resource estimate described herein and prepared in accordance with NI 43-101 will be filed on SEDAR www.sedar.com within 45 days from the date hereof.
To view tables and figures, please visit:
About Cardinal Resources Ltd
The Company is focused on the development of the Namdini Project with a recently announced Maiden Probable Reserve of 4.76Moz and is now advancing the feasibility study supported by additional multi-disciplinary engineering activities.
Exploration programmes are also underway at the Company's Bolgatanga (Northern Ghana) and Subranum (Southern Ghana) Projects.
Cardinal Resources Ltd