Aurizon Mines Ltd.: Gold Production at Casa Berardi to Commence in November 2006; Encouraging Drill Results From the Principal Zones
Friday November 10, 9:00 am ET
VANCOUVER, BRITISH COLUMBIA--(MARKET WIRE)--Nov 10, 2006 -- Aurizon Mines Ltd. (TSX:ARZ.TO - News)(AZK - News) confirms that the start up of operations at Casa Berardi is expected this month, following completion of the preproduction development work.
Casa Berardi Progress report
The mill is currently processing material from the surface stockpile of development ore and should be operating at the initial production rate of 1,600 tonnes per day by mid November, 2006.
Thereafter, mill feed will come from the underground stopes currently being developed. Mill throughput will gradually increase to 2,200 tonnes per day over the next twelve months in accordance with the feasibility study.
Preproduction work that remains to be completed prior to start up is as follows:
- Shaft sinking is complete and commissioning for the hoisting of ore, waste and personnel should be completed early next week.
- Surface construction of the main ventilation portal and associated underground infrastructure, which will significantly improve the underground airflow, should be completed in the next ten days.
- Backfill is critical to commencing mining operations. The cement plant, fill raise and underground slurry distribution is expected to be finished by mid-November. The fill raise collar and dump are complete. Sufficient waste fill rock material has been stockpiled underground to enable mining operations to commence.
- Mill rehabilitation and modifications are complete. Commissioning of the crushing and cyanide circuits is complete, and commissioning of the gravity circuit is proceeding with the processing of the surface stockpile of development ore.
- Underground stope preparation is in progress between the 650 and 730 metre levels on Zone 113. Forty six (46) access stopes are active, including 15 stopes that have been developed, drilled and are ready to be blasted.
Definition drilling of Zone 113
On Zone 113, where mining operations will commence, definition drilling continues along the 630 metre level drift. Zone 113 is usually wider in the central and western sections, where it is folded, and tends to be narrower along the flank in the eastern sections. Results are as follows:
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Thick- Thick-
Gold Gold ness Gold Gold ness
Defini- Ounces Grams Metres Defini- Ounces Grams Metres
tion per per (along tion per per (along
Hole tonne tonne the) Hole tonne tonne the)
# uncut uncut hole # uncut uncut hole
------------------------------------ ----------------------------------
Western and central section
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630-10 1.09 37.4 17.0 630-11 0.39 13.2 20.7
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630-03 0.86 29.8 11.2 630-05 0.31 10.8 9.7
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630-08 0.70 24.0 13.8 630-14 0.29 10.0 6.7
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630-13 0.65 22.2 18.6 630-09 0.23 8.0 3.6
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630-12 0.59 20.3 16.0 630-02 0.17 6.9 14.0
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630-07 0.43 14.6 13.0 630-04 0.12 4.2 7.2
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630-01 0.42 14.4 21.4 630-06 0.12 4.2 11.8
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Eastern section
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630-20 1.34 46.1 2.7 630-18 0.32 11.1 4.0
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630-22 20 41.2 5.5 630-19 0.25 8.7 4.6
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630-21 0.73 25.2 2.8 630-16 0.19 6.4 7.8
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630-24 0.45 15.4 4.1 630-15 0.18 6.2 7.2
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630-23 0.37 12.8 4.5 630-25 0.11 3.8 1.3
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630-17 0.23 8.0 10.0
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Zone 113 is interpreted to dip steeply to the south. The vein orientation and correlation between drill holes indicate that the system is nearly vertical. Definition drill holes are performed from each underground footwall drift, which are 20 metres apart. Holes along the drift elevation are flat, while holes between the drifts are dipping 5-10 degrees. This makes the true width of the system between 90% and 100% of the down hole intervals reported above.
Exploration drilling
Aurizon initiated a wide spaced exploration program in the area of the Principal Zones this summer with two drill rigs active on surface. In addition, one rig was active from underground along the dip extension of Zones 118-120. The Principal Zones, which host indicated mineral resources of 655,000 tonnes grading 6.2 grams of gold per tonne (130,000 ounces) and inferred mineral resources of 2.9 million tonnes grading 6.4 grams of gold per tonne (615,000 ounces), are not included in the current mining plan. The majority of the Principal Zones are located north of the Casa Berardi fault, 1,000 metres east of the new production shaft.
As shown on the geological cross section model attached to the press release, the location of the mineralization differs from the West Mine area. In the upper levels, mineralization is usually located on the northern side of the Casa Berardi fault. Between the 280 metre track drift and the 1,000 metre elevation, mineralisation tends to follow the contact between conglomerate and sediment units and moves away from the fault, resulting in moderate grades and widths. Below the 1,000 metre elevation, high grade mineralization is again encountered along the fault.
Zones 118-120 dip extension (mineralization along the fault)
Along the dip extension of Zones 118-120, mineralization is encountered within quartz veins and/or stockwork close to the contact with the Casa Berardi fault. Best holes in this area previously announced were 12.2 grams/tonne of gold over 7.2 metres and 7.7 grams/tonne of gold over 21.0 metres. A new hole, P22, returned 12.2 grams/tonne over 9.9 metres, including 31.3 grams/tonne over 3.6 metres. During the winter season, a surface drilling program will be initiated to test for a possible high grade core below the 1,200 metre elevation.
Mineralization at the contact between a conglomerate and sedimentary unit
The current drill program is testing the south side of the Casa Berardi fault, where most of the known economic zones in both the West Mine and East Mine are located. Mineralization has been encountered along the contact between a sedimentary and a conglomerate unit. Best holes returned 8.1 grams/tonne gold over 5.5 metres and 11.3 grams/tonne of gold over 7.1 metres.
Principal Zones
Two holes intersected the Principal Zones, north of the Casa Berardi fault and returned 29.7 grams/tonne of gold over 20.5 metres and 20.1 grams/tonne of gold over 1.5 metres.
Rehabilitation of the existing 280 metre level track drift, which connects the West Mine area to the shaft located at the East Mine, is budgeted for next year. The drift can then be utilized for an extensive underground exploration and infill drilling program. The main objective is to convert the existing mineral resources to reserves with an appropriate mining plan.
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Thick- Thick-
Gold Gold ness Gold Gold ness
Def- Ounces Grams Metres Def- Ounces Grams Metres
inition per per (along inition per per (along
Hole tonne tonne the) Hole tonne tonne the)
# uncut uncut hole # uncut uncut hole
-------------------------------------- ----------------------------------
118-120 Dip extension (high grade core)
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P22 0.36 12.2 9.9
including 0.91 31.3 3.6
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Principal Zones
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S245 0.87 29.7 20.5 S247 0.59 20.1 1.5
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Conglomerate-sediment contact
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P15 1.33 45.6 1.6 S244 0.12 4.0 3.0
0.07 2.3 6.3
0.06 2.1 2.6
0.06 2.0 8.0
-------------------------------------- ----------------------------------
P15A 0.13 4.7(2) 7.0 S245 0.10 3.5 5.7
0.16 5.5(1) 10.8 0.07 2.3 19.6
-------------------------------------- ----------------------------------
P19 0.06 2.1 22.4 S248 0.13 4.4 3.4
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P20 0.33 11.3(2) 7.1 S249 0.24 8.1(2) 5.5
0.66 2.1(1) 3.2
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P20B 0.11 6.0(2) 4.0 S251 0.13 4.4 3.2
0.17 5.8(1) 2.6
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P22A 0.08 2.7 11.5 S242 0.14 4.9 2.7
including 0.17 5.7 2.3
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Note (1) - Casa Berardi Fault
Note (2) - Contact between Conglomerate and Sedimentary Unit
Vein orientation and interpretation of mineralization between drill holes indicate that the Principal Zones and the high grade core follow the vertical structured trend of the Casa Berardi fault and indicate that the mineralized system is nearly vertical. The holes drilled from the surface have intercepted the Zones at an angle of approximately 45 degrees. This makes the true width of the system between 45% to 55% of the down hole intervals reported above.
The mineralization, which follows the contact between the sedimentary and conglomerate units, is interpreted to follow the structure steeply dipping to the south and locally follow the nose of a fold and its southern flank. Vein orientation and interpretation of mineralization between drill holes, indicate that the system is flat in the upper levels and dips moderately to the south in the deeper levels. This makes the true width of the system between 70% to 75% of the down hole intervals reported above.
Quality Control
Core assays are performed on whole core or core sawed in half, with standard fire assay procedures and atomic absorption finish. Certified reference material is inserted in the sample sequence for quality control. Assay checking on the pulp and reject samples are carried out systematically. Primary assaying is performed on site and check assays are carried out by ALS Chemex of Val D'Or, Quebec.
Drill hole planning, implementation and the quality control program is supervised by Jeannot Boutin, P. Eng., Superintendent Mining Geology, an appropriately qualified person as defined by National Instrument 43-101.
Additional Information
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