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The Taca Taca copper/gold/molybdenum project, comprising approximately 2,500 hectares, is located in the Puna region of north western Argentina in Salta province, approximately 230 kilometres west of the provincial capital of Salta and 90 kilometers east of the world's largest copper mine, Escondida.
Copper mineralization was first recognized at the Taca Taca Property in the mid-1960s and the property has previously undergone several exploration campaigns by Falconbridge, GAMSA, Corriente, BHP, and Río Tinto. The most recent activity prior to Lumina's current drill program involved drilling of eight diamond drill holes by Rio Tinto in 2008. A total of 29,036 metres of diamond and reverse circulation in 164 holes had been completed on the property at the end of the Rio Tinto program.
Hypogene, supergene and oxide porphyry Cu-Mo-Au mineralization at Taca Taca is typical of Andean porphyry deposits and is hosted by Oligocene granitic porphyry intrusions. Hypogene chalcopyrite mineralization is common beneath the quartz sericite altered portion of the porphyry and is capped on the west and north side of the porphyry by a zone of supergene enrichment. The supergene zone is generally 20 metres to 60 metres thick and consists of chalcocite and covellite coatings on hypogene chalcopyrite and pyrite. A 200 to 300 metre thick leached cap sits above most of the supergene zone and within this there are isolated occurrences of remnant (only partially leached) oxide/supergene mineralization that are dominated by chrysocolla, malachite, and brochantite. Other related types of mineralization identified on the property include exotic Cu-oxide occurrences beneath the Salar de Arizaro and Au-Cu quartz-hematite veins immediately to the north and west of the porphyry.
The recent recognition of hypogene high-sulfidation ("enriched") copper mineralization at Taca Taca may allow for significant tonnages of higher grade material to remain undetected within and below the current drill pattern provides a new rationale for targeting exploration. This zone of higher grade copper mineraliztion consists of bornite, chalcocite and digenite is considered to be the most attractive exploration target on the Taca Taca property.
The drill program conducted by Rio Tinto in 2008 intersected enriched, high grade copper in a number of drill holes and is highlighted by TTBJ-0007 which graded 426 meters grading 0.75% copper, 0.16 grams/tonne gold and 0.025% molybdenum (0.99% copper equivalent*) including 120 meters grading 1.40% copper, 0.21 grams/tonne gold and 0.035% molybdenum (1.73% copper equivalent*); TTBJ-0006 that returned 248 meters grading 0.89% copper, 0.11 grams/tonne gold and 0.036% molybdenum (1.16% copper equivalent*) and TTBJ-0003 that returned 195 meters grading 0.78% copper, 0.29 grams/tonne gold and 0.030% molybdenum (1.12'% copper equivalent*).* Copper Equivalent assumptions: Metal prices, US$1.50/lb Cu, US$600/oz Au and US$9.00/lb Mo. The formula used is as follows CuEQ= Cu% + (Au g/t x 0.583) + (Mo% x 6)
Previous to Rio Tinto's drill campaign only open-pittable copper had been targeted at Taca Taca but the high grade of copper mineralization encountered in Rio Tinto's drilling would allow underground exploitation by bulk mining methods. This represents a new deeper target type at the project. Consequently, a large area of the property now requires deeper exploration below the base of previous drilling.
Lumina filed an updated NI 43-101 compliant technical report, as amended on January 22, 2010, entitled "Amended Taca Taca Technical Report", on the property (the "Report") which can be viewed or downloaded from the link provided below. The Report was authored by Robert Sim, P. Geo., a Qualified Person as defined by NI 43-101. Additional work recommended in the Report included conducting preliminary metallurgical testwork, infill drilling within the current resource to reduce the average drillhole spacing to approximately 250 metres and exploration drilling to test for extensions of the deposit.
Following the results of the Report, Lumina completed a technical review to determine the appropriate development route for the project. This review included mine planning studies and an evaluation of the expansion potential of the existing mineral resource. The results of the review showed that potential additional value may be added to the project by extending the existing mineral resource to the north and identifying new areas of higher grade mineralization to the south and at depth and recommended that an exploration program be conducted.
In May 2010, Lumina commenced the exploration program with a deep ground penetrating geophysical survey utilizing Quantec Geoscience's proprietary Titan24 Deep Earth Imaging System to identify buried copper porphyry bodies. The Titan24 survey was completed in June 2010. In August 2010, Lumina commenced a first phase drill program to evaluate the deep targets generated from the Titan24 survey and potential northern extensions of the existing mineral resource. In addition, a preliminary metallurgical testing program was initiated to evaluate the amenability of the Taca Taca mineralization to flotation and concentration.
In 2011, the exploration and development program on the Taca Taca Property was expanded to include:
a drill program totalling approximately 99,500 metres, including geotechnical drilling;
a comprehensive metallurgical testing program; and
engineering studies, including mine planning, process engineering and design, infrastructure layouts and logistics including transportation, water and power supply.
Lumina's expectations are that the expanded exploration and drilling program will be completed during the second quarter of 2012.
On January 11, 2011, Lumina announced preliminary results from its initial metallurgical testing program which indicate that a high grade copper concentrate and a saleable molybdenum concentrate can be produced from both supergene and primary mineralized material.
On November 15, 2011 the company was pleased to announce that it had received an updated, interim mineral resource estimate. The estimate significantly increases the known sulphide copper, gold and molybdenum mineral resources and includes an initial estimate of the oxide gold resources contained in the leached cap.
The salient details of the updated National Instrument compliant ("NI 43-101") mineral resource estimate are as follows:
Sulphide Resources (0.4% copper equivalent cutoff*)
516 million tonnes grading 0.58% copper, 0.12g/t gold and 0.018% molybdenum (0.76% copper equivalent) in the Indicated category containing 6.6 billion pounds of copper, 2.1 million ounces of gold and 204.6 million pounds of molybdenum. Previously there were no Indicated resources defined.
880 million tonnes grading 0.43% copper, 0.08g/t gold and 0.015% molybdenum (0.57% copper equivalent) in the Inferred category containing 8.3 billion pounds of copper, 2.3 million ounces of gold and 292.9 million pounds of molybdenum. The previous NI 43-101 compliant mineral resource estimate contained 841 million tonnes grading 0.47% copper, 0.11g/t gold and 0.018% molybdenum.
(*) Copper equivalent calculated using US$2.00/lb Cu, US$900/oz Au and US$12.00/lb Mo and is not adjusted for metallurgical recoveries as these remain uncertain. The formula used is as follows: CuEQ = Cu% + (Au g/t x 0.583) + (Mo% x 6).
Oxide Resources (0.2g/t gold cutoff)
190 million tonnes grading 0.25g/t gold in the Inferred category containing 1.5 million ounces gold.
Within the sulphide mineral resource estimate, a shallower, higher grade supergene zone has been defined in the northern part of the deposit. The Company plans further work to investigate whether this high grade zone could form the basis of a "starter pit" for the project. This high grade zone, which remains open to the northeast and east, is defined as follows:
159 million tonnes grading 0.82% copper, 0.14g/t and 0.017% molybdenum (1.00% copper equivalent in the Indicated category (0.5% copper equivalent cutoff).
The updated mineral resource estimate remains open to the north, northwest, east, south, southeast and to depth. The Company is conducting a 99,500 meter drill program (47,308 drilled to date) to delineate the full extent of the deposit. The program currently has 6 drill rigs (5 core and 1 reverse circulation rig) operating and two additional rigs with greater depth capabilities are expected to arrive on site by the end of the year. The program outlined above is expected to be completed in April 2012 but will be extended or expanded further should additional mineralization outside the scope of the current program be identified.
An updated NI 43-101 technical report detailing the mineral resource estimate will be completed and filed on SEDAR and Luminas's website within 45 days.
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TACA TACA Porphyry Copper - Gold - Molybdenum Project, Argentina
NI 43-101 Technical Report
Effective Date: November 15, 2011
Execution Date: December 23, 2011
Authors and Qualified Persons:
Robert Sim P.Geo. (Principal Author)
Bruce Davis F AusIMM
[updated: NOV 2011]
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