Use of DEVICO Deep Drilling Technology at Rory’s Knoll (Aurora

Project), Guyana

Guyana Goldfields Inc.

The Country - Guyana

The Country - Guyana

• Only English speaking country in South America

• British common law, secure tenure

• Highly literate population of 700,000

• Pro-mining government

• Largely unexplored by modern methods

• Long history of significant gold production

History of Gold Exploration in the Guianas

“Guiana is a Country that hath yet her Maidenhead…not opened for gold, the mines not broken with sledges…”

Sir Walter RaleighThe Discovery of the Large, Rich and

Beautiful Empire of Guiana, 1596

Sir Walter Raleigh

The Region

The Guiana Shield

Aurora Property, GeologyAurora Property, Geology

Geology after Bracewell, 1949

Caleb’s East & West

Gold Creek

Property LocationsProperty Locations

Aurora PropertyAurora Property

The Golden MileThe Golden Mile

Aurora Base Camp

Golden Mile Mineralized Zones Diamond Drill Holes

Rory’s Knoll Diamond Drill Holes

Why DEVICO ?

• Constraint of 100 m x 150 m steep (70-75 deg) NNW-plunging Tonalite dimensions

• Historical left turns and consistent hole shallowing when drilling westwards due to regional foliation trend (NW)

• Problems with multiple wedging operations by Orbit drilling personnel

• Uncontrolled hole direction-wise

North East view of drilling operationsGrid (10mX10m) for a 680m target.

4 pilot holes and 36 directional cuts

DEVICO Requirements

• Rig capacity on total drilled depth

• RPM/WOB control• Mud Pump Capacity:

Flow Rate- 55 l/min Pump pressure- 60 bar

• Drilling mud pressure gauge & flow meter

• Mud pump accummulator / compensator (minimize pressure/flow rate pulsation)

• NQ-sized inner core barrel overshot / drill pipe sub

Long Section 10700E

Showing Lithology (plus blue-colored Devico directional

holes)

Long Section 10700E

Showing Assay Composites

Long Section 10750E

Showing Lithology (plus blue-colored Devico directional

holes)

Long Section 10750E

Showing Assay Composites

Long Section 10800E

Showing Lithology (plus blue-colored Devico directional

holes)

Long Section 10800E

Showing Assay Composites

Horizontal Plan View (-800 mRL)

Horizontal Plan View (-1000 mRL)

Devico directional factors

• Lithology (e.g. Ash Tuff Sediments)

• Structures (e.g. fault/foliation)

• Drilling parameters (e.g. hole azimuth & inclination)

• Target cone of influence specs per midpoint Devico target (e.g. up/down/left/right)

• DEVICO limits (e.g. high torque ~ 1000 m)

Devico-Orbit operations

• Rig mechanical problems (e.g. pump; etc.)

• Devico tool specs (e.g. thrust bearing; inner tube; etc.)

• Orbit-Devico drilling operations (e.g procedural; controlled drilling; etc.)

• Spare parts logistics

3-D View of Rory’s Knoll Mineralization

showing 100 m x 150 m Tonalite

dimensions (looking North)

3-D View of Rory’s Knoll Mineralization

showing 100 m x 150 m Tonalite dimensions

(looking East)

Devico-Orbit hole statistics

• RKD-60 mother hole: 9 directional cuts– Wedged/Devico-directed completed holes:

• RKD-60DV1/60DV2/60DV3L/60DV4R/60DV5R/• RKD-63B/RKD-67B/RKD-72B

• RKD-62 mother hole: 10 directional cuts– Wedged/Devico-directed completed holes:

• RKD-62DV1L/62DV2R/RKD-64/RKD-66/RKD-69/RKD-71/RKD-73

• RKD-63B/RKD-67B/RKD-72B

• Abandoned holes: – RKD-61A/61B/61C/RKD-63A/67A/72A

Summary

• 85 % Devico-hit on Rory’s Knoll mineralized zones on 19 medium to deep directional cuts proving mineralization is “open at depth”

• Cost-savings per hole (instead of drilling holes from surface): ~ 45-50% (estimated)

• Successful directional cuts are mainly dependent on drilling operations’ personnel teamwork and still improving !!!

• Once good Devico techs are spotted and with proven directional performance; don’t let go of them !!!