Devico in Zinkgruvan, Sweden

1. Devico in Zinkgruvan,Sweden

2. Zinkgruvan mine • Owned by Lundin Mining • Zinc • Lead, silver, copper • Greatly folded mineralization • Ore body varies from 700 to 1200m vertical depth

3. Previous drilling • New discovery • Few and spread boreholes • BQ-TK core drilling • Effective • High unstable deviation

4. Devico in Zinkgruvan • Contact late 2006 • Delineate the new discovery • Time saving • Accuracy

5. Devico in Zinkgruvan • Started in May 2007 • Old 56mm borehole, 65° inclination • Reamed to 76mm and sidetracked at 630m • Targets at 900 to 1200m depth • Second drill rig in August 2007 • Old 56mm borehole, 69° inclination • Reamed to 76mm and sidetracked at 330m • Targets at 700 to 1000m depth

6. Sidetracking • Initial sidetracks from 56mm to 76mm • DeviDrill • Corac core barrel • Other sidetracks • Cut out of curve • 2-3 wedges

7. Cut the curve

8. Borehole steering • 100m between targets • 30 - 50m directional drilling initially • Up to 150m total steering to hit one target

9. Precision • 5 or 10m target limits, less in certain directions • At times, 3 corrections in one hole • Corrections down to 1050m depth

10. Target hit angle • Sidetracked boreholes gets inclination of 45°-80° • Sometimes parallel with ore body  Deep inclination changes • 15 degrees and more • 60m or more

11. Results • 12-13 sidetracks • New mother hole under planning • Satisfied geologist! • “From the beginning people were talking about production gain and cost gain with Devico but this aspect of being able to chase the ore horizon when the geology decides to disobey, gives me as a geologist a much easier job and better health”