MRG Metals Sheds Light on Recent Outstanding Poiombo Assay Results
Jun 22, 2020
It sure has been great few weeks for heavy mineral sands (HMS) explorer MRG Metals Limited ASX:MRQ as it advances target areas of the Corridor Projects, Mozambique. To name a few- promising results of a Mineral Resource Estimation (MRE) from its first target area, Koko Massava along with confirmed extension of mineralised footprint, new HMS targets in the form of Siaia and Viaria, highest to date THM grade at Zulene, and most impressively- best overall Aircore drill hole results for the entire Corridor Central and Corridor South project areas from Poiombo.
MRQ’s Recent Milestone at Poiombo
The Company notified on 18 June 2020 that new lab assays of Aircore samples from Poiombo have delivered outstanding high-grade HMS intersections over substantial lateral and vertical extents, highlighting robust continuity of high-grade HMS mineralisation across strike as well as laterally at the target.
The update fetched massive attention and response from shareholders and mining enthusiasts who sent in their queries asking for more details about the outstanding Poiombo Assay results. So much so, MRQ was riding high on the ASX, up by 12.5 % and quoted $ 0.009 a share on 19 June 2020.
Quenching queries, MRG Metals has promptly provided the full suite of assays for Aircore holes 20CSAC355 (the best Aircore assaying an uncut 36m @ 7.09% THM from surface to end of hole, with two consecutive 3m sample intervals yielding >16% THM) and 20CSAC356 (with an average uncut result of 51m @ 5.40% THM, with a maximum grade of 14.82% THM in the interval 33-36m).
Breaking Down Impressive Results from 20CSAC355 & 20CSAC356
Aircore holes 20CSAC355 and 20CSAC356 provided one of the bests results from Poiombo’s Aircore drilling assays. They are 500m away from each other on a drill line at the southwest end of Poiombo (that was defined from a magnetic anomaly). Each of the holes comprise of thick intervals of excellent high-grade HMS mineralisation.
Let us get a detailed result break down for these holes-
The best hole from the lot (20CSAC348–357), 20CSAC355 was drilled to 36m depth, comprising 12 primary samples (2035501- 2035509; 2035511-2035513) along with one field duplicate sample (2035510). By wet panning, concentrating the heavy mineral, field visual estimates of THM% were logged from ~ 20g grab-sample, stemmed from greater 20-25kg primary sample. Field estimates of THM% are moderate to high (2.0%–6.7% visTHM) between 0-24m, correlating with laboratory data of 2.96%– 6.57% THM
Between the interval 24-33m downhole, higher estimated grades (7.3%–7.8% visTHM) are logged and correlate with laboratory results of 10.18%–16.80% THM
A lower estimated THM% of 5.2% is demonstrated by the final sample interval 33-36m, correlating with laboratory result of 6.23% THM
The field duplicate sample 2035510, submitted ‘blind’ to the laboratory, returned a grade of 16.42% THM. This relates very well to 2035509, paired primary sample, with grade 16.38% THM.
The Company also notified that field estimated grades in higher grade zone (24-33m) were underestimated. Correlation pattern (moderate and high) among estimated grades and lab grades exits.
Another significant hole, 20CSAC356 was drilled to 51m depth, comprising 17 primary samples (2035601- 2035617) wherein drill sample interval was 3m in length.
Field estimates of THM% between 0-30m depth are moderate to high (1.8%–7.2%), correlating well with laboratory results of 2.22%–5.41% THM.
Between interval 30-39m higher estimated grades are logged (8.0%–19.5% visTHM), correlating with higher laboratory assay results of 8.42%–14.82% THM
Field estimated grades reduce to 1.4%–5.7% visTHM from 39-45m downhole, correlating with laboratory results of 2.87%–5.79% THM
Final two sample intervals between 45-51m demonstrate field estimates of 8.0% THM, correlating with laboratory results of 5.68% and 7.21% THM
The Company further explained that higher grade zone was overestimated in field logs. Nonetheless, zones of moderate, high as well as higher grades within field estimates continues to correlate well- same pattern in lab results.
Strandline-style HMS Mineralisation
At hole 20CSAC355, it is clear that strandline-style HMS mineralisation occurs between 24- 30m depth. Similarly, at hole 20CSAC356, it is clear that strandline-style HMS mineralisation occurs 500m northwest between 33-36m depth.
Above results are derived via very high grades reverted from lab assays. Moreover, difference in depth down hole of strandline zone (high grade) has the possibility of being related to differences in elevation of collars. MRG Metals affirmed that strandline mineralisation is connected to surface with high to moderate THM grades and strike of mineralisation is possibly northeast-southwest, sub-parallel to the Poiombo magnetic anomaly.
However, additional drilling will determine the validity of this interpretation. It will further show if mineralisation persists at very high grade among the two holes as well as along strike.
Management Remark
Acknowledging the receipt of numerous enquiries seeking further clarification on Poiombo’s exceptional results, Chairman, Mr Andrew Van Der Zwan stated that results showed some variation from field visual estimates of the same intervals previously reported (in some very high grade holes). Formal lab assay results have been authenticated and aided in the identification of the importance and geological significance of identified strandlines.
He further stresses on the fact that visual field estimates should be used as a guide, though them matching formal assay results would be great, yet not achievable.
Details Continue
MRG Metals wishes shareholders and market to understand that significant effort is made to provide the best field estimated THM% grades. This includes use of images showing panned samples with associated assay grades. A consistent grab sample mass utilised for every panned sample as well as retrospective comparisons of lab data with field estimates.
Though, field estimation as well as uniformity of estimation among particular loggers remains tricky amid 5-10% THM and very tricky >10% THM.
Aircore Drilling Details
On Aircore samples, Western GeoLabs led heavy liquid separation (HLS) analysis wherein they were oven dried, disaggregated (if needed). Later, samples were weighed plus split to ~100g sub-samples.
Post being wetted and attritioned, the sub-sample was de-slimed (at 45µm) to assess slime per cent. Screened at +1mm, the +45µm-1mm fraction experienced HLS with tetrabromoethane (specific gravity being 2.95).
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