projects

Bambana

Overview

During the 2009/2010 season, Calibre advanced the copper-gold Bambana prospect, located in northeastern Nicaragua, to the diamond drill stage to test for potential copper-gold porphyry and skarn mineralization. The Bambana prospect is located within the 100% Calibre owned Rosita D concession, four kilometres northwest of the historic Rosita copper mine. The Rosita mine is a copper skarn deposit that is estimated to have produced 305 million pounds of copper, 177,737 ounces of gold, and 2,629,720 ounces of silver over its 25+ year mine life*.

Calibre has executed an option agreement with Alder Resources Ltd. (TSX-V: ALR) ("Alder") whereby Alder can earn a 65% interest in the 3,356 hectare Rosita D concession (the "Property") located within Calibre's 100%-owned Borosi concessions in northeast Nicaragua. Located within the Property is the historic Santa Rita open pit copper-gold mine and the Bambana copper-gold prospect. Under the terms of the option agreement, Alder can earn a 65% interest in the Rosita D concession by expending a total of CDN$4.0 million on exploration and other work on the Property and by issuing to Calibre a total of 1,000,000 common shares of Alder over a 4 year period. Alder will be acting as the project operator for all work conducted on the Property during the option period with the first year exploration commitment being CDN$500,000. Upon Alder earning a 65% interest in the Property a joint venture will be formed with Calibre and Alder being responsible for their pro-rata share of all subsequent project expenditures. The option agreement is subject to a 45 day due diligence period by Alder from the date of execution of the agreement.

* Historical production from (Arengi 2002).

Geology

The Bambana area is underlain by the tertiary aged Matagalpa Group andesitic volcanics and minor pyroclastic rocks along with associated intermediate to felsic intrusions, many of which form overlapping coeval volcano-plutonic centers. The Bambana target has the potential for hosting porphyry and skarn style mineralization within a multi-phase intrusive center (quartz monzonite to granite) which lies in contact with Mesozoic Todos Santos Formation calcareous sediments. This geologic setting is similar to the one found at the Rosita Mine.

Drilling Program

In 2010 Calibre completed three drill holes totalling 859.4 metres (Figure 2). The first two holes targeted a 500 metre x 300 metre area containing strong overlapping Cu+Au geochemical and geophysical anomalies (Figures 3-4), as well as numerous artisanal gold and prospecting pits (Figure 5). Significant drilling results from this area included 0.43% copper over 42 metres (BB10-001) and 0.51% copper over 11.50 metres (BB10-002) (Table 1). A third drill hole targeted the northeastern intrusive-sediment contact but failed to cross the contact and returned no significant results.

No exploration work is currently planned for 2011 but the property remains an intriguing exploration target based on the significant copper intercepts returned in BB10-001 and BB10-002 (Figures 6-7).

Hole ID From (m) To (m) Interval (m) Au (g/t) Ag (g/t) Cu (%)
BB10-001 71.00 73.50 2.50   28.15 1.05
BB10-001 79.00 121.00 42.00     0.43
BB10-002 58.10 58.65 0.55 9.02 75.50 0.11
BB10-002 75.40 86.90 11.50 0.25 10.41 0.51
BB10-002 75.40 78.62 3.22 0.23 21.81 1.15
BB10-002 83.15 86.90 3.75 0.55 12.39 0.54
BB10-003

No Significant results

Summary of diamond drill results 2010.



Figure 1. Geology and rock sampling highlights for the Bambana target area.
Figure 2. Map showing geology, drill hole locations and Cu soil results for Bambana target area.
Figure 3. Drill hole locations and Cu soil results on top of Rosita IP chargeability data.
Figure 4. Drill hole locations and Cu soil results on top of Rosita Magnetometer TMI data.

Figure 5. Copper mineralization (malachite and azurite) in granite. Photo taken in prospecting pit at surface.
Figure 6. Fine-grained to blebby pyrite and chalcopyrite in groundmass and mafic sites of K-sp rich altered granite (88.50m - BB10-001).
Figure 7. Bornite blebs in secondary biotite-rich groundmass of potassic altered granite (28.10m - BB10-001).