COPPERSTONE RESOURCES AB: DRILLING CAMPAIGN ACCOMPLISHED AND CAUSATIVE PORPHYRY STOCK LOCATED CENTRAL TO WIDESPREAD COPPER MINERALISATION
Published 23 August 2018
Copperstone Resources AB (“Copperstone” or “the Company”) is pleased to announce that the planned exploration drilling campaign at Granliden is complete on time and budget. A total of 10 deep NQ drill holes (7,616m) were accomplished over a period of 7.5 months, representing approximately 95% of the planned 8,000m. A second campaign of NSAMT has also been completed this summer.
An update will be provided at the end of September 2018 when all final laboratory results are expected to be received. The final report on the drilling campaign is expected towards the end of November 2018.
3 drill holes have found an undiscovered porphyritic felsic intrusive. This zoned complex is a wide dyke-like stock with a probable northeast-southwest trend and is believed by the geological team to be the likely causative intrusive for the surrounding chalcopyrite mineralisation. At least 3 separate intrusive phases are present within the stock. The full extent and shape of this body is not yet known and will require more drilling to map out.
Within the altered tuff-lava geology outside the porphyritic intrusive complex, all remaining 7 drill holes have located broad copper mineralisation zones with some intercepts up to 80-85m drill width. It is likely that the full extent of the copper-gold mineralisation is significantly larger than previously known. Note that the true width, continuity and full extent of the mineralisation system is not yet known and further drilling is required to determine if any mineral resource potential exists. There can be no guarantee than any future drilling will define any mineral resources at all.
Preliminary analysis of incomplete laboratory results received to date shows that composite grades should typically range from 0.1-0.6% Cu, across the broader mineralisation envelopes. High grade copper values (typically 1-3%) are also present in narrow lode veins present either within the low grade envelopes, or as isolated lodes. Laboratory work is still ongoing to determine composite width and grade of intercepts. In some drill holes sampling intervals need to be extended as the shape and internal pattern of these envelopes is becoming more apparent.
The single drill hole east of Granliden hill on section line 4 has found at drill depths of approximately 500m a broad zone of hydrothermal hematite veinlets with localised veinlets containing bornite. This may represent proximity towards the central stock. Similar hematite –magnetite development is also found around the edges of the inner granitic phases of the stock complex.
Sphalerite (zinc) mineralisation associated with thick pyrite veining (Eva-style) has been located in an isolated area east of Granliden Hill and along with gold-bearing arsenopyrite seems to form a broader metalliferous halo to the copper mineralisation as originally thought.
An additional 478 NSAMT readings have been made extending the original grid southwards beyond Eva and northwards from Granliden Hill. In total the survey now covers 4.4km north-south by approximately 2.5km east-west. Work is ongoing to model this data and generate a complete 3D resistor image for the property. Early analysis shows that there is a significant deep conductor under the Svartliden mineralised area that will need to be drill tested.
The drill programme has been concentrated along 4 x east-west exploration lines covering the area to the east of Granliden Hill and deep under the historic shallow drill holes. Exploration lines are roughly 200m apart with most drill holes collared either west or east. The campaign has examined all the main geophysical targets defined in this area.
“Our 8,000m drill campaign is complete as we planned and the results are very encouraging. We set about looking for proof-of-concept for the porphyry genetic model, and that is exactly what we have found. This is an important step in our quest to demonstrate that the porphyry model and its large-scale hydrothermal mineralisation potential does indeed exist on our property. There is an outer altered zone, an inner coarser granite phase and so far a third porphyry body with large fragments of granite that have been brought up from greater depth. It’s a complex body, previously unknown and to me looks every inch the smoking gun.
Besides the new geology we have uncovered, all our drill holes have found significant copper mineralisation envelopes both west and east of the porphyry complex. We are still working on the sampling, definition of these mineralisation envelopes and possible shapes. Without doubt the copper mineralisation is much more extensive than was previously known. It will take more exploration to work out those answers and this campaign is an excellent foundation for that. Grades are in range of something really credible to explore further, and it is not without good reason to say now that this could be a big copper system at large.Our work is ongoing and over the coming months we will work on the vast amount of new data and bring that to a conclusion by early winter.
Our team has put in an incredible effort to do this and I’m sure this campaign is not only a major value-add to our Company but is also a major contribution to the geology of the Arvidsjaur Arc and is adding great credibility to finding big hydrothermal systems here in Sweden.” comments Chris McKnight CEO of Copperstone.
For further information, please contact Chris McKnight (CEO) at +46(0)580-88890, or firstname.lastname@example.org or refer to Copperstone webpage: www.copperstone.se.
This press release contains insider information which Copperstone Resources AB (publ) is obliged to publish according to the EU market abuse regulation (MAR). The information was delivered by the above mentioned contact for publishing 23rd August 2018 at 0745 CET.