Duke Exploration : New Geophysical Modelling and Drilling Update

DRILLING UPDATE AT QUORN AND ISENS PROSPECTS

PROSPECTIVITY AT BUNDARRA AND

NEW GEOPHYSICAL MODELLING DEMONSTRATES EXPANDED

17 December 2021

Media Release

ASX ANNOUNCEMENT | ASX: DEX

onlyuseDuke Exploration Limited (ASX: DEX) ("Duke" or "the Company") is pleased to announce the results of new geophysical data processing and drill target ranking at the Bundarra project in Central Queensland, consistent with Duke's previously outlined pluton-wide expanded and accelerated exploration strategy. Very encouraging preliminary observations from new diamond drilling at Quorn and Isens prospects are also reported.

personal			HIGHLIGHTS
	• New modelling of historical airborne EM data was completed. A total of 39 km of linear
			conductive trends were identified through this targeting analysis from which 19 km were
			associated with anomalous copper in soil.
		•	Duke geologists have incorporated this newly processed geophysical data into a
			prospectivity model for the area with very encouraging results.
		• Conductivity highs were detected that correlate with known mineralisation and copper in
			soil anomalies, as previously predicted.
		• Multiple other conductivity anomalies with associated copper in soils exist that have not
			been tested by drilling and represent priority targets.
For		• Quorn diamond drill hole intersects visible copper mineralisation in breccia and vein style
		zones.
	• Isens diamond drill hole intersects copper sulphide bearing alteration zone down-dip from
		historic workings.

Commenting on progress - Philip Condon, MD:

"The completion of the historic VTEM data remodelling using up-to-date technology, represents the next significant step in Duke's expanded Bundarra resource development strategy, building on the recently completed and very successful Bundarra pluton-wide geochemical soils survey. The interpretation of the results and integration into the exploration model is now generating further focused and refined target identification and prioritisation, as planned. The next very exciting stage is

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Managing Director

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Toko Kapea

Chairman

Philip Condon

This announcement has been authorised for release by the Board.

[e-mail]

Ph+64 27 534 2886

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the drill testing of the generated primary targets, which has begun with the Quorn and Isens holes having been completed and sent for assay, and 3 diamond holes remain to be drilled on the Rogers prospect. Our initial diamond drill hole at Quorn is very significant as it confirms the potential for bulk- style breccia hosted copper mineralisation in the Bundarra area in addition to the vein styles seen in the same prospect and at Mount Flora. This is a very important and positive outcome of our revised

onlystrategy in action, as there are now two distinct styles of mineralisation that have been identified and confirmed to be present at Bundarra. Duke will continue to advance the understanding of geology and mineralisation at Bundarra with mapping and drill testing of targets into Q1, 2022."

Future Work Program

Future work planned at Bundarra includes:

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• Further detailed ground checking and geological mapping in vicinity of priority targets.

• Diamond drill testing of best conductivity anomalies.

• Further diamond drilling in Quorn area

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Technical Information

VTEM Data Modelling and Coincidental Geochemical Anomalies

Duke Exploration has interpreted historic Versatile Time-Domain Electromagnetics (VTEM) data that was acquired onlyover the Bundarra area in 2011 by previous owners of the project. VTEM data was reprocessed by TechnoImaging LLC of Utah, USA, who are experts in providing 3D imaging solutions of a variety of geophysical data, including airborne electromagnetics. TechnoImaging utilised their proprietary EMVision® software and GlassEarth® technology to produce a 3D model of conductivity and chargeability to a depth of 300 m below surface covering most of the Bundarra project area. When combined with Duke's soil sampling data, the 3D geophysical model highlights numerous coincidental conductivity and copper in soil anomalies around the Bundarra pluton's 50 km

long contact.

useThe announcement on 15 September 2021 outlined Duke's profile targeting system that utilised conductivity derived from processed Gradient Array IP (GAIP) data and pXRF copper in soil results to define the location and likely size of mineralisation targets around the Bundarra pluton. Processing the historic VTEM data and extending oil surveys has allowed the technique to be further modified and applied over an expanded area where there was no GAIP coverage. Figure 1 demonstrates the utility of the processed VTEM data at Mount Flora, where the modelled higher conductivity response is correlated with mineralisation in fresh rock at a depth of approximately

70 m below surface. The new processing allows both the horizontal and vertical extent of conductors to be personaldefined by manually examining successive depth slices (at 100 m, 170 m and 240 m) through the 3D conductivity model. A set of linear trends were digitised on each depth slice to define conductive zones (Figure 2), which were

then correlated with surface copper in soil anomalies. For

Figure 1. Section 7,572,270 mN of the most northern line of resource drilling relative to pXRF soil

and electrical geophysical anomaly profiles

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Figure 2. Interpreted linear trends form pXRF copper soil and conductivity profile targets from survey areas

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A total of 39 km of linear conductive trends were identified through this targeting analysis from which 19 km were associated with anomalous copper in soil (Figure 2). The majority of conductive trends associated with copper in soil anomalies are untested by drilling. The large scale of the combined geophysical and geochemical anomalism provides excellent exploration potential.

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personalThe interpreted VTEM conductivity inversion model data was added to Duke's spatial prospectivity database that includes data from soil samples, drilling results, historic workings, defined resource and exploration target size.

Prospect areas are defined by polygons, which are weighted according to the strength of the various inputs, e.g. higher copper in soil assays contribute to a higher rank for a prospect. Rankings are relative and allow Duke geologists to assign priorities for drill testing. Geological mapping and assessment of the highest ranked targets Forhas begun to help guide RC drill-testing planned for early 2022. Figure 3 shows a total of 74 outlined prospect areas that are colour coded by their prospective ranking with red highlighting the top ten that will be given priority.

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personal	Figure 3: Identified prospective areas colour coded by red - high prospectivity and blue - lower prospectivity

Quorn and Isens Preliminary Exploration Drilling Results

As reported in the announcement of 5 November, five diamond holes for 880 m were planned at Quorn, Isens and Rogers to test the exploration targeting technique outlined above. These holes were designed to:

• Test selected high priority coincident copper in soil and zones of high Gradient Array Induced Polarisation (GAIP) conductivity,
• Collect petrophysical downhole survey data to map geological and structural geometries,
• Review and categorise the relevant rock classes present downhole,
• Review orientations of structures and mineralisation downhole, and
• Review and interpret the geometry and controls on the copper and silver mineralisation intersected to date.

ForTwo holes (one hole at Quorn and one hole at Isens) have been completed, with three holes remaining to be drilled at Rogers (Table 1 and Figure 4). Drilling was severely impacted by adverse weather conditions and will continue into January 2022.

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