25 to 45 million tonnes at 0.7 - 0.9g/t Au and 2 - 3g/t Ag,
for a total between 0.56 to 1.3Moz of Au and 1.6 to 4.3Moz of Ag.
In accordance with Clause 18 the JORC Code, when considering the Exploration Target readers are advised "the potential quantity and grade is conceptual in nature, that there has been insufficient exploration to define Mineral Resources and that it is uncertain if further exploration will result in the determination of a Mineral Resource" 1.
The quantity and grade of the exploration target is based on upper and lower limits applied to an unconstrained block model with varying search distances to reflect the upper and lower tonnage ranges. The block model was derived from existing historical drill hole information and used surface geochemistry as a guide for extrapolation. The block models were reported at various Au cut-offs, with a 0.4g/t Au cut-off used for this study.
Additional drilling is required to confirm the results generated by previous explorers whose data is yet to be fully validated. To achieve this Artha has planned approximately 2000m of diamond drilling which is due to commence when a suitable rig becomes available.
Artha's CEO, Charles Straw, stated that:
"Whilst the exploration target is conceptual in nature at Organullo it is supported by a relatively large amount of historical drilling and associated exploration work such as mapping and surface sampling. Organullo is undoubtedly a large mineralizing system and the result of this work justifies additional drilling at the project. Further exploration work is required to ascertain the full potential of the property."
Salta Province has a stated aim of attracting more exploration and mining investment and has been described as a new frontier for mineral exploration. Currently there are many projects at an advanced stage of exploration or in feasibility mode. These include the El Quevar silver project, Lindero gold project, Daibillos silver-gold project, Rio Grande copper project, the Lumina copper project and many others.
The Lindero gold project located in Salta Province is considered a comparable project to Organullo and has measured and indicated resources of 71.9 million tonnes grading 0.74 grams/tonne Au at a 0.4 grams/tonne Au cut-off, containing 1.71 million ounces of gold. The project has received a mine permit to build a heap leach operation treating up to 11Mt p.a. A full feasibility study is underway and will be based on a heap leach gold mine operating at 4.3Mt p.a using a cut-off grade of 0.4 grams/tonne Au.
The Organullo project is located in Salta province in northwest Argentina approximately 20 kilometres due south of the village of San Antonio de Los Cobres and approximately 100km W-NW from the provincial capital, Salta. Access is easily attained by a network of roads through the central part of the property. The project area ranges in height from 3900m to 4500m and is characterized by relatively steep valleys and ridgelines.
Artha has entered into an Option Agreement whereby it can earn an undivided fifty-five (55%) percent working interest in the interest of Cardero Argentina S.A. ("Cardero Argentina") in the tenures which make-up the Organullo Project, and thereafter form a Joint Venture with Cardero Argentina, a wholly owned subsidiary of Cardero Resource Corp. ("Cardero"). In November 2011 a NI-43-101 Technical Report was completed on the property as part of the Option Agreement with Cardero. Artha have undertaken geological and structural mapping in conjunction with rock chip sampling at Organullo which has confirmed and enhanced prospectivity of the Project. More recently Artha engaged GeoRes Consultants to review and model existing drillhole data at the project for the purposes of estimating an 'exploration target' pursuant to the JORC Code. GeoRes have also made recommendations regarding future work at the project.
The earliest recorded work in the area of the Organullo property was from small-scale production at the Julio Verne mine during the 1930's. Mining activity centered on 2 high-grade sub-parallel veins with concentrates reported to average 12.5% bismuth and 8.2% copper with gold ranging between 10-20 g/t. Early regional work was undertaken in the area by Fabricaciones Militares in 1962-72 in partnership with the United Nations, followed up by an IP survey and drilling of one core hole by Cities Service Corporation for which no data exists. In 1994-1995 Triton Mining Corp. and Northern Orion Explorations, Ltd. jointly conducted a detailed surface sampling, mapping and prospecting campaign and completed a 17-hole, 3,295-metre RC drill program. This was followed with a 6 hole diamond drill program in 1997 and an additional 12-hole RC drill program in 1999 by Northern Orion. During this time a total of 1046 surface samples were collected and analyzed. These were mostly outcrop chip or channel samples.
Cardero purchased the project in 2004, and conducted several reconnaissance exploration programs and collected 504 surface rock chip and channel samples. Other work included CSAMT, Aster interpretation and ground magnetics. In 2010 Cardero completed an 8 hole 2,053m diamond drilling program and completed petrographic and PIMA studies. A summary of the drilling data is presented in Table 1.
Table 1: Drilling Summary
|Company||Year||RC Holes||RC meterage||Core Holes||Core hole meterage||Drill Assays|
|Triton Mining Corp||1995||17||3095||3081|
|Triton Mining Corp/Orion Exploration Ltd.||1997||6||1013.8||587|
|Orion Explorations Ltd.||1999||12||2012||1004|
|Cardero Resource Corp.||2010||8||2053.5||1417|
Geology and Mineralization
Gold mineralization on the Organullo property is hosted in Tertiary age dacite to andesite volcanic/volcaniclastic rocks and their subvolcanic intrusive equivalents, as well as underlying Pre Cambrian aged Puncoviscana metasedimentary rocks. Quartz veins, stringer zones and silicified zones with disseminated pyrite and some sulphosalts are commonly associated with faulted, brecciated and fault gouge zones proximal to dacite intrusives and generally return the highest gold values. The mineralization at the Julio Verne mine has been classified as a high sulphidation epithermal style mineralization, even though this local setting does not exactly fit the classic model for high sulphidation style mineralization. The mineralization on Organullo Ridge can also be classified as a high sulphidation epithermal system, although this is not unequivocal due to the early level of understanding of this system. More recent work is more suggestive of low, intermediate and high sulphidation alteration assemblages.
Exploration Target - Notes
Robin Rankin (the GeoRes Consultant), was engaged in April 2012 by Artha Resources Corporation to evaluate the scale of potential gold and silver exploration targets at Artha's Organullo Project in Argentina. Topographic and drill hole data had previously been databased by GeoRes in 2011.
Objectives: The objectives of this Project were to evaluate the scale of potential exploration targets at Organullo and to achieve this in an initial limited sense by utilizing "unconstrained" grade modeling utilizing drill hole data generated by previous explorers. To assist this process geological and geochemical data generated by Artha and previous workers was also utilized to assist with extrapolation parameters.
Data: Data was supplied electronically by Centric Minerals Management on behalf of Artha. Topographic data was sourced via the internet from the USGS. Existing work and geological understandings on the Organullo Project was essentially described in a geological report to Artha of 11th April 2012 by BISA, a mining project development, management and consulting company based in Lima, Peru. Exploration drill hole data was exported from the Artha MS Access database and supplied in spreadsheet form and databased in GeoRes's mining software package Minex. The data has not been verified and the project has not been visited by the Consultant.
Geological understandings and project implementation: From the BISA report the Consultant understood that the gold mineralized system at Organullo was very dominantly connected to and occurring within (or at least very close to) brecciated epithermal quartz veins and enclosing altered country rock. Veins were generally fairly planar, mostly steeply dipping and often sub-parallel, and occurring in groupings by area and also by strike directions. The majority of veins either fall into a NNE striking group or a NNW/NW striking group. Mineralization of interest is gold and silver with the tenor of silver values ~ twice the gold values.
The implementation strategy adopted was to identify where veins could be characterized by a single common strike and dip direction; identify the areas where exploration targets could be evaluated for a common vein dip and strike; model grades into unconstrained (not differentiated by geology) 3D blocks; and estimate block grades in each area by using strong anisotropy to simulate continuity in the plane of the common vein strike and dip direction.
Modeling: GeoRes determined two common strike and dip directions, each characteristic in a specific exploration target area: Strike 020