Gervaise Heddle, Chief Executive Officer, commented:Truly spectacular results – a world-class drill intersection
“We are thrilled by these truly spectacular results which further demonstrate the exceptional potential of Havieron. These stunning results represent a world class intersection as measured by total mineralisation in one drill hole in excess of 1,500 metre grams gold equivalent. Elevated gold and copper results persisted to end of hole suggesting the mineralisation continues at depth below the current limit of drilling, which is supported by the results from forward modelling of detailed geophysical data.
“The remarkable peak gold and copper grades of 211.3gt/t and 8.45% respectively are significantly higher than in previous drilling. Importantly, we have seen significant widths of copper well in excess of 0.5%.
Greatland announces drill hole HAD005 intersects total mineralisation (combined intercepts) of
275m at 4.77g/t gold and 0.61% copper (275m at 5.75g/t gold equivalent*)
Two wide zones of mineralisation intersected:
118m at 3.08g/t gold and 0.84% copper from 459m (118m at 4.42g/t gold equivalent*),
157m at 6.04g/t gold and 0.44% copper from 660m (157m at 6.75g/t gold equivalent*).
Further to the announcement made on 1 October 2018, Greatland Gold plc (AIM:GGP), the precious and base metals exploration and development company, is delighted to announce exceptional laboratory assay results from the Company’s first drill hole (HAD005) of the current campaign at its 100% owned Havieron licence in the Paterson region of Western Australia.
Highlights of HAD005 Drill Results:
· Total combined intercept of 275m at 4.77g/t gold and 0.61% copper returned from:
· An upper zone of 118m at 3.08g/t gold and 0.84% copper from 459m to 577m, including:
o 11.5m at 6.23g/t gold and 2.49% copper from 462.5m; and
o 7.5m at 32.83g/t gold and 1.20% copper from 482m.
· A lower zone of 157m at 6.04g/t gold and 0.44% copper from 660m to 817m, including:
o 113m at 8.30g/t gold and 0.61% copper from 663m;
o 5.5m at 16.62g/t gold and 0.91% copper from 663m; and
o 38m at 20.17g/t gold and 0.82% copper from 700m.
· Upper and lower zones separated by an unmineralised mafic intrusion from 577m to 660m.
· Results significantly extend the known high grade mineralisation established in the first drilling campaign and establish new peak grades for the mineralised system, including peak gold of 211.30g/t (previously 137.69g/t) and peak copper of 8.45% (previously 4.11%).
· Multiple notable high-grade intervals in both upper and lower zones including:
o 0.5m at 64.1g/t gold and 5.38% copper from 464.5m, and
o 0.5m at 202.76g/t gold and 0.83% copper from 486.5m, and
o 0.5m at 211.3g/t gold and 3.56% copper from 487.5m, and
o 1m at 97.65g/t gold and 8.45% copper from 702m, and
o 4m at 103.82g/t gold and 0.86% copper from 713m.
*Gold equivalent values are calculated using a copper conversion factor of 1.5998 from a copper price of US$2.80/lb and a gold price of US$1,200/oz.
Greatland’s first drilling campaign at Havieron, carried out in April-May 2018, yielded excellent results, which included 121m at 2.93g/t gold and 0.23% copper from 497m, including 11.5m at 21.23g/t gold and 0.67% copper from 568.5m (HAD001), and 21m at 3.79g/t gold 0.44% copper from 418m (HAD003). The current drilling campaign at Havieron (Greatland’s second drill campaign), which commenced on 17 September 2018, includes plans for up to a total of approximately 6,000 metres of drilling.
A regional map showing the Havieron licence area with regional targets and adjacent landholdings can be found at: http://greatlandgold.com/paterson/
Overview of Paterson Project, Havieron licence and HAD005 Drill Results
The Company’s Paterson project, comprising the Havieron, Black Hills and Paterson Range East licences, is located in the Paterson region of northern Western Australia. The three licences collectively cover more than 385 square kilometres prospective for iron-oxide-copper-gold (“IOCG”) type deposits and Telfer style gold deposits.
The Paterson region hosts several large gold and copper deposits such as Telfer and Nifty. The region has been subject to more recent exploration which has outlined several other deposits including Magnum (Au), Calibre (Au), O’Callaghans (W, Cu) and Maroochydore (Cu).
The region is remote, however infrastructure is good with several operating mines, roads, formed tracks and rail networks nearby which branch out from the regional industrial hub of Port Hedland 500km to the west.
The Paterson Province is the northern portion of the Proterozoic Paterson Orogen. More recent exploration throughout several Proterozoic Orogens within the western parts of the Australian continent has resulted in the discovery of the large Tropicana gold deposit and the large Nova nickel-copper deposit. Globally these Proterozoic Orogens are highly prospective for large deposits and are often under-explored.
Alteration and mineralisation of those targets which have been drill tested at Havieron and Paterson Range East display affinities with IOCG-type deposits. Examples of these are the large Olympic Dam and Ernest Henry deposits in central and eastern Australia.
Initial airborne data outlined the Havieron target as covering approximately 1,000m x 1,000m. Depth to top of target is around 400m with these depths easily achieved with modern drilling equipment. Historically only six drill holes were completed by Newcrest between 1991 and 2003, all of which intersected significant hematite alteration and gold, plus copper anomalism. Thick lower grade zones of gold and copper were intersected and gold grades within these peaked at 15.4g/t and copper to 2.5%. The drill hole spacing was broad and the core of Havieron therefore represented an immediate resource definition drilling target.
Following a review of regional geophysical and geochemical data over the Paterson project approximately 50 IOCG-like targets were identified in the broader region, with around half in ground held by Greatland. The setting of these licences is on the western margin of a Proterozoic basin which ranges in depth from less than 100m below surface to more than 400m below surface. Basement rocks of the basin are predominantly calcareous rich sandstones intruded by several late stage granitic bodies exploiting basin margin faults which have also provided a focus for ore fluids. Historically, several of these targets were subject to initial first-pass work and show promise at hosting mineralisation as seen at Havieron. The geophysical signature of these targets is very similar to that at Havieron. Basement rocks do not outcrop and Greatland intends to employ modern geophysical and geochemical methods to define targets prior to drill testing. The Scallywag target was identified from this regional review and hosts several magnetic anomalies over an area of approximately 6km x 4km with potential to host gold and/or copper mineralisation.
MMI sampling and ground gravity over the Havieron target was completed in late 2017 at an initial sample and station spacing of 200m x 200m. Additionally ground gravity was completed over the Scallywag target at a station spacing of 400m x 200m. Results of ground gravity and MMI work at Havieron has outlined several targets for a 2018 drill campaign with the peak gravity response not tested by existing drilling. Gravity confirms a NW structural trend of basement carbonate sediments which is mirrored by the surface MMI response. Clusters of elevated gold, silver, arsenic, copper and iron in MMI results are proximal the peak co-incident gravity and magnetic response. An elevated MMI response in pathfinder elements (cerium, lanthanum, uranium and lead) to the immediate SE of Havieron suggests primary basement mineralisation may be present along strike in a structural contact for up to 1.5 kilometres. Peak MMI responses over Havieron were 4ppb silver, 70ppb arsenic, 25ppb gold, 834ppb cerium, 710ppb copper, 53ppm iron, 284ppb lanthanum, 860ppb lead and 112 ppb uranium. Elevated pathfinder elements detected by the MMI survey support the view that Havieron is an IOCG-like system.
Forward modelling of detailed aeromagnetic data (50m line spacing and 40m mean terrain clearance) and detailed ground gravity data (100m x 100m and 100m x 200m station spacing) over the Havieron target was completed in February 2018 by independent geophysical consultants. Results of forward modelling defined a primary body approximately 600m x 600m across with a depth extent from 400m to 900m below surface resulting in a potential volume of more than 240,000,000 cubic metres and an estimated mass of more than 650,000,000 tonnes. A second smaller body with a volume of more than 16,000,000 cubic metres lies immediately adjacent to the primary body. Results of forward modelling are indicative only as geophysical data is ambiguous, however modelled bodies were constrained to known physical rock properties and therefore potentially represent the core of the mineralised system at Havieron. Forward modelling suggests that of the six historic drill holes completed at Havieron only two intersected the target. Those two holes intersected only the very top of the modelled mineralised system but returned over 100m of mineralisation (HAC9101) and over 50m of mineralisation (HAC9201) peaking at 15.4g/t gold and 2.5% copper within broad, lower grade intercepts.
In April and May of 2018, Greatland carried out its maiden drill campaign at the Havieron target completing four vertical core holes (HAD001-004) for a total of approximately 2,400m of drilling. Greatland’s drill locations were designed to intersect the mineralised system at Havieron near to historical drill holes HAC9101 and HAC9201. Newcrest’s historic drill holes HAC9101 and HAC9201 were vertical and drilled to depths of 533m and 528m respectively. Significant results were returned including 121m at 2.93g/t gold and 0.23% copper from 497m, including 11.5m at 21.23g/t gold and 0.67% copper from 568.5m (HAD001) and 21m @ 3.78g/t gold and 0.44% copper from 418m, including 1m at 29.12g/t gold and 0.4% copper from 428.5m (HAD003).
The company re-commenced drilling at Havieron in September 2018 (as announced 17 September 2018) with the intention of completing approximately 6,000m of drilling. The first hole of the new program (HAD005) was completed at the end of September to 821.2m and it was reported to market (1 Oct 2018) that approximately 239m of mineralisation was present, visibly similar to that intersected in HAD001.
HAD005 was sited 200m west of HAD001 and angled at 70 degrees toward grid east. The hole was designed to intersect the base of HAD001 and continue at depth. HAD005 intersected recent desert sands and Permian siltstones and sandstones from surface to 459m before immediately entering the mineralised Proterozoic target sequence. From 459m to 577m (118m) mineralised brecciated calcareous limestone and sandstone with massive pyrite, chalcopyrite, pyrrhotite and quartz veining is present. From 577m to 660m (83m) an unmineralized mafic intrusion is observed. From 660m to 782m (122m) mineralised brecciated calcareous limestone and sandstone with sulphides (as per 459m to 577m above) continues, and from 782m to 821m (39m) laminated calcareous sandstone with sulphide mineralisation is present. Significant alteration within the mineralised zones is apparent. HAD005 end of hole was 821.2m.
Analytical results for HAD005 have been received and are reported here. Overall, an intercept of 275m at 4.77g/t gold and 0.61% copper was returned (1,581 metre grams gold equivalent*) from an upper zone of 118m at 3.08g/t gold and 0.84% copper from 459m, and a lower zone of 157m at 6.04g/t gold and 0.44% copper from 660m, separated by an apparently unmineralised mafic intrusion. Other intercepts include 7.5m at 32.83g/t gold and 1.20% copper from 482m, 0.5m at 211.30g/t gold and 3.56% copper from 487.5m, and 0.5m at 64.1g/t gold and 5.38% copper from 464.5m. Plus 38m at 20.17g/t gold and 0.82% copper from 700m, 4m at 103.82g/t gold and 0.86% copper from 713m, 1m at 97.65g/t gold and 8.45% copper from 702m, 1m at 138.74g/t gold and 1.24% copper from 714m, and 1m at 200.75g/t gold and 0.73% copper from 715m. All intercepts over 1g/t are presented in Table 1. Other metals are present in the mineralised system including silver to 211g/t, zinc to 5.9% and lead to 12%.
As in HAD001, elevated gold and copper results persisted to end of hole suggesting the mineralisation continues at depth below the current limit of drilling, which is supported by the results of forward modelling of detailed geophysical data. These results demonstrate the presence of very high grades of gold and copper at Havieron, and when considered in conjunction with geophysical models, the potential large scale of the mineralised system at Havieron is apparent.
Drilling is ongoing, and the Company will continue to review results in conjunction with detailed geophysical and geochemical data. Downhole wireline work is also being carried out to assist with geological interpretation and refinement of geophysical models.
Additional information on the Havieron, Black Hills and Paterson Range East licences can be found on the Company web site at www.greatlandgold.com/projects.
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