Azure Minerals Limited

Promontorio

Figure 1: Promontorio Project
Figure 1: Promontorio Project
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Figure 2: Deposit Geology
Figure 2: Deposit Plan
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Azure holds the rights to acquire 100% of the Promontorio project in Chihuahua, Mexico.  Promontorio is an advanced stage project hosting a deposit with a JORC Code resource and several nearby prospects.  This acquisition meets Azure’s strategic objective to secure a high quality, advanced stage project with early cash flow potential.

The Promontorio project comprises the adjoining Hidalgo, Promontorio & Magistral mineral concessions which together cover 187 hectares.  Azure will pay US$4.0 million over four years to acquire the concessions, with an option to bring forward payment at any time to secure immediate full ownership.  No royalties are payable to either vendors or government.  Azure also holds the surrounding 120km2 mineral concession.

Azure has completed an initial diamond drilling program of 40 holes totalling 6,695m, and produced a JORC Code mineral resource of 502,000 tonnes @ 4.7% copper, 2.1g/t gold & 99g/t silver at a 1% copper cut off, containing a total of 23,400 tonnes of copper, 34,000 ounces of gold and 1.6 million ounces silver.  Full details of the resources classification and estimation methodologies are detailed in Azure’s announcement to the ASX, released on 7th January 2009. 

The deposit is a high sulphidation epithermal type consisting of multiple massive and semi-massive sulphide veins containing very high grades of copper, gold and silver.  From west to east there are three main veins – Santiago, Mina Vieja and Veta Grande – interspersed with several other, un-named, mineralised veins.  All veins have a north-south strike, dip steeply to the west, and possess good geological continuity.

The mineralised structure outcrops over at least a 1,000m strike length before becoming obscured by more recent cover rocks.  The deposit was drilled over a strike length of only 200m and to depths of about 150m, and remains open-ended along strike to the north and south and at depth.  Wildcat drilling 340m to the north of the deposit intersected further high grade copper, gold, silver and molybdenum mineralisation, thereby demonstrating the excellent opportunities for significant expansion of the resources in these areas.

Azure has commenced a pre-feasibility study with initial metallurgical testwork on a bulk sample of Promontorio ore being completed in early 2009.  The testing program included head grade analysis, mineralogical examination, comminution testing, sulphide flotation testwork, a recommendation on the optimum process route to produce a copper concentrate, and preliminary evaluation of various downstream processing options for treatment of the copper concentrate.

First stage flotation tests produced a “rougher” concentrate grade of 23.1% copper, with a recovery of 99.4% of the total copper into a mass recovery of 48%.  Further flotation testing upgraded the rougher concentrate to produce a “cleaner” concentrate grade of 33.9% copper with a recovery of 98.2% of the total copper, and reduced the mass recovery to 34%.  More details of metallurgical results are contained in Table 1.

Table 1
Bulk Composite Rougher & Cleaner Recovery Results
PRODUCT MASS COPPER SILVER GOLD ARSENIC
  Recovery
(%)
Grade
(%)
Recovery
(%)
Grade
(ppm)
Recovery
(%)
Grade
(ppm)
Recovery
(%)
Grade
(%)
Recovery
(%)
Rougher
Conc
48 23.1 99.4 365 98.9 6.7 97.6 6.6 99.7
Cleaner
Conc
34 33.9 98.2 377 93.5 6.9 83.2 6.9 99.3
Comminution Testing Results
Optimum Grind Size:  P80 @ 106μm
Rod Mill Work Index (kWh/t):  18.5 (moderate)
Ball Mill Work Index (kWh/t):  17.2 (moderate)
Abrasion Index: 0.6 (moderate)
Indicative Processing Route
  • Conventional crushing, grinding & flotation
  • Alkaline leach of concentrate to remove arsenic
  • Transport arsenic-free concentrate to 3rd party smelter

Also present at the project is the Cascada prospect which hosts a near surface zone of gold-silver mineralisation, with wide zones (>10m) of moderate grade gold (1-2g/t) indicating the potential for a bulk tonnage gold deposit.  A best intercept of 7.6m @ 19.8g/t gold highlights the potential for bonanza-grade gold mineralisation.

Other major deposits in the district include the Ocampo Mine (reserves of 2.5Moz gold and 113Moz silver), the Pinos Altos Project (reserves of 2.5Moz gold and 73Moz silver), the Dolores Mine (reserves of 2.4Moz gold and 127Moz silver), and the Palmarejo Project (resources of 1.7Moz gold and 150Moz silver).

 

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