26th Feb 2015 07:01
Herencia Resources plc
("Herencia" or "the Company")Picachos Delivers Maiden Resource
Potential to significantly boost Resource grade and tonnage
Highlights
· Picachos Project maiden Mineral Resource estimate delivered for the 40M Shaft area with a global Resource measuring (at a 0.1% and 0.2% Cu cut-off grade respectively):
§ 10.7Mt at 0.61% copper and 5.6g/t silver (at 0.1% Cu cut-off)
§ 7.1Mt at 0.85% copper and 7.6g/t silver (at 0.2% Cu cut-off)
· The Resource includes a higher grade core of:
§ 3.4Mt at 1.12% copper and 9.6g/t silver (at 0.85% Cu cut-off).
§ 56% of the high grade core in the Measured and Indicated categories
· Resource to potentially underpin the first 3-5 years of open pit mining at Picachos.
· The maiden Resource covers only a small area within the 40M shaft area of the Picachos tenement
· Two near surface zones of potential mineralisation identified adjacent to 40M Shaft area.
· A new zone of mineralisation located between the 40M Shaft and Flor del Bosque has not been included within the Resource Estimate (RC hole PP14049 returned 19m at 1.83% copper and 17.9g/t silver).
· The 40M Shaft area maiden Mineral Resource remains open in ALL directions and is situated within a geological sequence containing multiple limestone strata, the main host for copper-silver mineralisation.
Herencia Resources plc (AIM:HER), the Chile-focussed mineral exploration and development Company, is pleased to announce the maiden Resource Estimate for the Picachos Copper Project ("Picachos" or the "Project") in northern Chile. The Mineral Resource estimate has been prepared in accordance with the JORC Code 2012.
The Picachos stage two drilling program consisted of 36 drill holes totalling 5,998 meters - with five diamond cored holes (DDH) totalling 1,239 meters and 31 reverse circulation (RC) holes totalling 4,759 meters. The drilling targeted two separate styles of mineralisation - the higher grade structures and the lower grade manto or stratabound mineralisation.
Marco Alfaro Consulting, a Chilean resource estimation service group based in Santiago and experienced in a broad range of Chilean copper deposits (including Picachos style stratabound mineralisation), undertook the resource estimation work.
A digital 2D section model of the Picachos project was initially prepared by Herencia's geologists, consisting of nine N30°W cross-sections at 50 meter intervals. These 2D geological sections were then reviewed by the resource consultant and a solids model generated using the 2D sections. A block model was then created using block dimensions of 5m x 5m x 5m and the Ordinary Kriging geo-statistical method ("OK method") was used to calculate the copper and silver mineral resource estimate.
The Mineral Resource estimate for Herencia's Picachos Project (40M Shaft area only), is shown in the table below. Herencia currently holds an option over 100% of Picachos*:
Picachos Project - Mineral Resource Estimate (February 2015) | ||||||||||||
Cut-off Grade | Measured | Indicated | Inferred | Total | ||||||||
%Cu | Kton | Cu % | Ag (g/t) | Kton | Cu % | Ag (g/t) | Kton | Cu % | Ag (g/t) | Kton | Cu % | Ag (g/t) |
0.10 | 2,221 | 0.88 | 7.68 | 1,690 | 0.86 | 7.65 | 6,824 | 0.46 | 4.43 | 10,735 | 0.61 | 5.61 |
0.20 | 2,176 | 0.89 | 7.79 | 1,678 | 0.86 | 7.69 | 3,240 | 0.82 | 7.33 | 7,094 | 0.85 | 7.56 |
0.30 | 2,116 | 0.91 | 7.93 | 1,656 | 0.87 | 7.76 | 3,023 | 0.86 | 7.69 | 6,795 | 0.88 | 7.78 |
0.40 | 2,018 | 0.94 | 8.13 | 1,600 | 0.89 | 7.90 | 2,947 | 0.88 | 7.81 | 6,564 | 0.90 | 7.93 |
0.50 | 1,855 | 0.98 | 8.44 | 1,495 | 0.92 | 8.15 | 2,810 | 0.90 | 7.99 | 6,160 | 0.93 | 8.17 |
0.55 | 1,760 | 1.01 | 8.61 | 1,429 | 0.94 | 8.29 | 2,677 | 0.91 | 8.15 | 5,865 | 0.95 | 8.33 |
0.60 | 1,651 | 1.03 | 8.82 | 1,354 | 0.96 | 8.44 | 2,535 | 0.93 | 8.32 | 5,540 | 0.97 | 8.50 |
0.65 | 1,544 | 1.06 | 9.02 | 1,267 | 0.98 | 8.60 | 2,362 | 0.96 | 8.52 | 5,172 | 0.99 | 8.69 |
0.70 | 1,432 | 1.09 | 9.24 | 1,165 | 1.01 | 8.80 | 2,197 | 0.98 | 8.70 | 4,794 | 1.02 | 8.88 |
0.75 | 1,320 | 1.12 | 9.45 | 1,060 | 1.03 | 9.01 | 1,995 | 1.00 | 8.91 | 4,375 | 1.05 | 9.10 |
0.80 | 1,197 | 1.16 | 9.71 | 944 | 1.07 | 9.25 | 1,776 | 1.03 | 9.13 | 3,917 | 1.08 | 9.34 |
0.85 | 1,074 | 1.20 | 9.99 | 814 | 1.10 | 9.54 | 1,500 | 1.07 | 9.40 | 3,388 | 1.12 | 9.62 |
0.90 | 945 | 1.24 | 10.31 | 697 | 1.14 | 9.84 | 1,270 | 1.10 | 9.66 | 2,912 | 1.16 | 9.91 |
0.95 | 842 | 1.28 | 10.60 | 599 | 1.18 | 10.13 | 1,028 | 1.15 | 9.97 | 2,469 | 1.20 | 10.22 |
1.00 | 746 | 1.32 | 10.90 | 499 | 1.22 | 10.44 | 824 | 1.19 | 10.26 | 2,069 | 1.24 | 10.53 |
The Mineral Resource Estimate was undertaken by Mr. Marco Alfaro. Mr Alfaro is an Independent Consultant and has sufficient experience relevant to the style of mineralisation and type of deposit under consideration to qualify as a Competent Person as defined in the JORC Code.
* see announcement dated 7 August 2013
One challenge associated with 'Picachos-style' mineralisation is how best to calculate the resource without unreasonably diluting the higher grade structures. The resource consultant concluded that the Ordinary Kriging methodology, used to determine the current resource, appears to accurately reflect the total copper within the resource however produces a 'smoothing' that in all likelihood results in an overestimation of the lower grades and an underestimation of the higher grades. A follow up drill program, planned to take place prior to mining, will provide further drill density and assay data and is expected to further improve the grade profile.
The maiden resource covers only a small portion of the Picachos tenements as seen in the following link http://www.rns-pdf.londonstockexchange.com/rns/8987F_-2015-2-25.pdf, with most drilling less than 100 metres deep vertically. The resource remains open in all directions and the mineralisation looks to extend to over 1,200m in length, judging by both the drilling results and the current mining locations. This is further supported by an area of significant mineralisation discovered between the 40M Shaft and Flor del Bosque that has not yet been included in the maiden Resource Estimate. A drill hole in the area PP14049 returned 19m at 1.83% copper and 17.9g/t silver from close to the surface. There is a strong possibility this mineralisation is the northern extension of the 40M Shaft deposit which would significantly extend the strike extent of the mineralisation in the resource.
In addition to the Mineral Resource estimate, a review of the geological model and the drilling results has identified several new target areas with considerable untested potential for higher grade tonnes. The targets are located to the east, immediately adjacent of the 40M Shaft with mineralisation outcropping on the surface and which coincide with a geophysical Induced Polarisation (IP) high. The IP survey was conducted in 2014 (see RNS dated 20 November 2014) and the area contains numerous shallow and high grade mine workings.
A limited drill campaign, planned prior to mining commencement, will assist in determining the potential extent of this mineralisation. Should these areas result in additional economic mineralisation, the overall strip ratio for the planned open pit would significantly decrease. The untested targets are located within a younger copper-rich limestone sequence and are clearly outlined in the two cross-sections shown in the following link http://www.rns-pdf.londonstockexchange.com/rns/8987F_1-2015-2-25.pdf.
Managing Director, Graeme Sloan, commented on this latest milestone:
"This is a great result for the Company and shareholders alike, and the outcome of a huge amount of work and commitment by our Chilean team who have worked tirelessly to develop a maiden Resource within a very tight schedule .
The results not only validated our geological model but importantly delivered a larger than expected maiden Mineral Resource estimate.
The new target areas identified immediately east of the 40M Shaft mineralisation could really add to the open pit mine model. The area has multiple historic and recent shallow mine workings in the area which is a great start. If the drilling turns up economic mineralisation it would almost certainly fall within our open pit mine shell, decreasing the strip ratio even further..
Over 50% of the high grade core of the Resource sits within the higher confidence Measured and Indicated categories with most potentially accessible by open pit mining methods.
The Resource will now be used in our open pit optimisation work, utilising the mining costs recently submitted by several experienced open pit mining contractors, and will form the basis of our detailed open pit mine designs.
Our target is to be in production as quickly as possible, with some of the cash flow generated directed towards systematically exploring the many other target areas within Picachos and to progressively expand mining and copper production (and cash flow) by bringing multiple open pits on line.
The Resource is a major milestone for the Company and leaves us with little doubt that Picachos has the potential to develop into a significant copper deposit."
About the Picachos Project
The Picachos Project is located approximately 50km south east of the coastal city of La Serena, 8km west of both the existing Andacollo copper-gold project operated by Teck Resources and the mining town of Andacollo (population approximately 10,000 people), and 10km south of the privately owned Tambillos copper mine. The Project is very well positioned for infrastructure with existing high voltage power located approximately 3km east of the Project area and serviced by two all-weather access roads.
Small scale mining is currently being undertaken by private miners via small open pit and underground mining operations. High grade ore is being trucked to a Chilean government owned processing plant (ENAMI plant) where it is processed. This mining will continue up until such time as the Option to fully acquire Picachos is exercised (at Herencia's discretion) and is seen by the Company as an excellent mechanism to achieve geological and grade data across many zones of mineralisation.
A review of available data and Herencia's own geological and drilling programs have confirmed multiple zones of copper mineralisation with a combined strike length of over 8km contained within the Project area. In some areas the close relationship of these zones coupled with multiple occurrences of out-cropping wide zones of mineralisation, highlights the excellent potential for large scale open pit mining to take place at Picachos. Historic mining has focused mainly around the high grade structures, however in some areas the mantos have been mined up to 50m wide. Mineralisation generally commences from one to five metres below the surface and appears open at depth.
About Herencia
Herencia Resources plc, is an AIM quoted exploration and development Company operating in Chile. In addition to the Picachos Copper Project, the Company also has the Guamanga Copper Project and the 70% owned Paguanta Project, a high grade silver-zinc-lead project located in northern Chile.
The Company's corporate office is located in Perth and the main technical and management office is located in Santiago, Chile where it has been operating for over eight years.
For further information, please contact:
Graeme Sloan, Herencia Resources plc +61 8 9481 4204
Katy Mitchell, WH Ireland Limited +44 161 832 2174
The information in this report that relates to Mineral Resources is based on information compiled by Mr Marco Alfaro, a Competent Person who is a Member or Fellow of The Australasian Institute of Mining and Metallurgy.
References in this announcement to Mineral Resources and exploration potential have been approved for release by Mr Graeme Sloan (BAppSc Mining Engineering WASM) and Mr Marco Alfaro (Civil Engineer [Mining] Universidad de Chile and Doctor of Mining Technical Sciences [Majoring in Geostatistics] MINES ParisTech), both who have more than 20 years relevant experience in the field of activity concerned. Mr Sloan is a full time employee of the Company. Mr Alfaro is employed by Marco Alfaro Consultores. Mr Alfaro has sufficient experience relevant to the style of mineralisation and type of deposit under consideration and the activity being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the 'Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves'. Mr Sloan and Mr Alfaro have consented to the inclusion of the material in the form and context in which it appears.
Glossary of Technical Terms:
Ag | Silver |
Cu | Copper |
Cut-off | the lowest assay included in an estimate |
DD | Diamond Drill |
g/t | grams per tonne |
JORC Code | Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves, as published by the Joint Ore Reserves Committee of the Australasian Institute of Mining and Metallurgy, Australian Institute of Geoscientists and Mineral Council of Australia |
Kt | thousand tonnes |
Ordinary Kriging | An interpolation technique used in geostatistical and resource modelling |
RC | Reverse Circulation |
Further background details on the Company can be found at www.herenciaresources.com
**ENDS**
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