7704364d-89c8-448a-8803-98fc1dd43c27.pdf
STRATEGIC MINERALS
CORPORATION N.L.
8th December 2015 ASX Release
Woolgar Gold Project, Queensland
(Strategic Minerals Corporation N. L. (Strategic) 100%)
Resource Update for Big Vein South
The Company is pleased to announce a resource update on the Big Vein South gold deposit (BVS) in the Lower Camp of the Woolgar Project in North Queensland. This update follows the earlier release of the Resource Update for Big Vein South and Central prepared in May 2015. Both updates have been prepared by H&S Consultants Pty Ltd (H&SC), an independent consultancy, on behalf of Strategic and are reported according to the 2012 JORC Code & Guidelines.
HIGHLIGHTS INCLUDE:
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A global resource of 10.24Mt at 2.03 g/t, containing 667,000 oz. gold at a 0.75g/t cut-off.
Category
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Mt
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Au g/t
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Au Kozs
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Density t/m³
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Measured
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0.17
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2.17
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12
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2.59
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Indicated
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4.38
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2.01
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283
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2.69
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Inferred
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5.69
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2.03
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371
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2.71
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Total
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10.24
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2.03
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667
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2.70
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Resource update incorporates the recent drilling that successfully tested the previously announced exploration targets between the two existing resources, see Figure 1.
Down dip extension of the Flat zone
Southern zone
Northern zone
Flat zone
Central zone
Figure 1: Geological Interpretation of the Mineral Zones at B, showing drillhole locations and the focus of the recent drilling = black circle.
Strategic Minerals Corporation N.L. ASX Code: SMC
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58 Jersey Street, Jolimont Western Australia, 6014
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www.stratmin.com.au [email protected]
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ACN: 008 901 380
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P.O. Box 66
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(08) 9284 1255
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ABN: 35 008 901 380
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Floreat Forum. WA 6014
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(08) 9387 7331
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Substantial exploration potential to delineate further resources, with an Exploration Target at a 0.75g/t Au cut-off of 10 to 20Mt at 1.8 to 2.1g/t for 0.75 to 1.25Moz. The potential quantity and grade of the Exploration Target is conceptual in nature, that there has been insufficient exploration to estimate a Mineral Resource and that it is uncertain if further exploration will result in the estimation of a Mineral Resource.
Southern
Central
Northern
Northern
Central
Southern
Flat
Figure 2: December 2015 BVS Resource Estimate: Gold Block Grade Distribution.
Upper figure: View looking down to grid northwest. Lower figure: View looking down to grid south east.
Big Vein South (BVS) Resource Summary: December 2015
H&S Consultants Pty Ltd ('H&SC') was requested by Strategic Minerals Corporation NL ('Strategic') to complete updated resource estimates for the Big Vein South ('BVS') gold deposit of the Woolgar Project. The project is located in North Queensland, approximately 120km north of Richmond. H&SC had completed new resource estimates for the deposit in May 2015. The updated resource estimates have been reported according to the 2012 JORC Code & Guidelines.
The BVS mineralisation comprises deformed, auriferous, quartz-sulphide veins with pervasive silica alteration. Host rocks consist of Proterozoic-aged, amphibolite grade quartz-feldspar-biotite-mica schists within a ductile deformation zone. The type of mineralisation is a mesothermal vein style. Structurally the deposit appears to be controlled by an upright sigmoidal development during ductile deformation with subsequent brittle offset faulting producing three main zones. A fourth zone appears as a splay structure to the Northern zone of the main sigmoidal structure.
Strategic supplied the drillhole database for the deposit, which H&SC accepted in good faith as an accurate, reliable and complete representation of the available data. H&SC loaded the data in to an Access database that was then connected to the Surpac mining software. H&SC performed limited validation of the data including error checking, and completed some data processing to improve the database and enable easier geological interpretation. The drillhole database for the BVS deposit is satisfactory for resource estimation purposes; however responsibility for data quality resides solely with Strategic. Drilling for the deposit is predominantly RC with some additional Diamond core drilling.
Historical drilling has consisted of five phases undertaken from 2010 to 2014 amounting to 224 drillholes for a total of 24,067m and 23,790 samples. Drillhole spacing is variable from 15m, generally targeting near surface mineralisation, to 50-100m along strike and down dip. The new drilling, completed in September 2015, comprises 13 RC holes for 2,968m and 2,839 samples. 11 holes drill tested a previously defined Exploration Target associated with the Central zone, along with the adjacent northern edge of the Southern zone, the southern edge of the Northern zone and part of the Flat zone. This drilling was generally on 50m centres.
Quality Control
The QAQC programme has included the use of sample weights, certified standards for gold, field duplicates, lab duplicates, umpire lab checks, screen fire assays and fire assay checks on roasted samples. QAQC results have indicated no significant issues with the sampling or assaying. Screen fire assay checks have indicated no significant coarse gold. There is no relationship between gold grade and RC sample recovery. The roasting analyses indicated no refractory gold.
Geological Modelling
The new drilling (see black circle in Figure 1 above) has resulted in minor changes to the geological interpretation for the mineral lodes. The Central zone has been interpreted slightly wider than anticipated, but now includes the previously noted hangingwall mineralisation, albeit of generally lower grades. Both the Southern and Northern zones also appear to be wider at their northern and southern ends respectively. The Flat zone was confirmed but it has been extended in a steeper down dip direction adjacent and parallel to the Northern zone. The mineral wireframes are based on using logged geology, sulphur, silver and aluminium assays, a nominal gold cut-off grade of 0.1g/t, and interpretation of magnetic data and geological sense.
The mineral wireframes were used to extract a total of 4,162 2m composites for subsequent gold grade interpolation. The composite length represents a change from the original May 2015 resource estimate and is more a reflection of the increased width of the main mineral zones. Experimentation with applying top cuts to the gold composite data indicated that no top cutting was considered necessary. Variography indicated reasonable downhole and directional grade continuity. The Central zone composite data exhibited a flatter than expected down dip directional structure which may be related to higher grade zones formed as part of the sigmoidal growth associated with the dilatant structure responsible for the mineral body formation.
Grade interpolation used Ordinary Kriging (GS3M software) with the resultant models loaded into a Surpac block model. Domaining was limited to the individual mineral zones and to the variations in spatial orientation i.e. geological dip and strike, of sub-sections of the more complex Southern zone. Modelling used the same expanding search pass strategy as for May 2015, with the initial search radii based on the localised detailed drill spacing, increasing in size to take in the geometry of the mineralisation and the variography. Modelling consisted of two estimation runs, the first with 2 passes and the second with 2 passes. The minimum search used was 4m by 15m by 15m and expanding by 15m increments in the Y and Z directions to a maximum of 60m (and up to 16m in the across strike, X, direction). The minimum number of data was 12 samples and 4 octants. A fifth pass was completed to assist with the Exploration Target generation, whereby the maximum
number of data was reduced to 6 and 2 octants whilst keeping the 16m by 60m by 60m search. An additional estimation run of a further 3 passes was also used to further assist with generating an Exploration Target with the maximum search of 10m by 125m by 125m and a minimum of 3 data and 1 octant.
Default density values for mineralisation and waste rock were derived from 274 samples (using the Archimedes method) including 101 fresh rock mineral and 19 oxide mineral samples. Allocation of density grades and oxidation levels to the block model was achieved by using the mineral wireframes, volume adjustment values and oxidation surfaces in relation to the block centroid.
Resource classification is based primarily on the drillhole spacing (and hence the data point density), grade continuity (variography), the geological model and the QAQC data. The resource estimates are reported for a 0.75g/t Au cut off with a partial percent volume adjustment generated by the constraining mineral wireframes. Less than 2.6% of the deposit tonnage is in the oxide zone with just under 2% of the ounces. The new resource estimates are tabled below with examples of the block grade distribution shown in Figure 2 above.
Resource Update -Big Vein South
Table 1: Resource tonnages by category, December 2015.
Category
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Mt
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Au g/t
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Au Kozs
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Density t/m³
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Measured
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0.17
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2.17
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12
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2.59
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Indicated
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4.38
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2.01
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283
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2.69
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Inferred
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5.69
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2.03
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371
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2.71
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Total
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10.24
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2.03
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667
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2.70
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The new resources estimates represent a 65% increase in tonnes with a 5% drop in grade and a 57% increase in the number of ounces. The vast majority of this has come from the newly defined Central zone which was the prime target for the recent drilling. The May 2015 modelled figures for the Central zone Passes 5- 8 were 4.2Mt @ 1.76g/t for 238,500ozs, the new drilling has partly tested the Exploration Target yielding an estimate figure of 2.8Mt @ 2.08g/t for 189,750ozs. Additions to the new resource estimates have come from the other three zones. The number of gold ounces in the Northern zone has been increased by 36,000ozs (approximately 82% increase) due to higher grades associated with a substantial thickening in the deposit at its southern end. There is a 40% increase in ounces for the Flat zone (9,400ozs) mainly due to the newly interpreted steeper down dip extension, whilst the Southern zone has increased by 5,500ozs (a 1.5% increase).
The majority of the resource seems to occur as a flattish east dipping zone at depths of 100 to 150m below surface as noted in the above figure.
Figure 3 and Figure 4 below show the new resource estimates relative to the May 2015 figures. The newly defined Central zone is clear to see along with the substantial thickness increase associated with the southern end of the Northern zone.
Validation of the block model consisted of visual comparisons of block grades with the drillhole data, a review of the global statistics for composites and block grades and a review of a previous resource estimate. Validation confirmed the modelling strategy as acceptable with no significant issues.