Dokwe Project: Results of detectORE™ Trial

Ariana Resources plc ("Ariana" or "the Company"), the AIM-listed mineral exploration and development company with gold project interests in Africa and Europe, is pleased to announce the completion of field trials of a ground-breaking new analytical technique at the Dokwe Project site in Zimbabwe.

Highlights:

• Reliable gold analytical results obtained from drill core in as little as 15 hours (with dry sample), using detectORE™.
• Over 1,000 samples were successfully tested and cross-checked by an ISO-accredited laboratory.
• Gold correlations from detectORE™ versus laboratory results ranged from good to excellent (0.72 to 0.99 R2).
• A fully operational low-cost and relatively mobile detectORE™ laboratory has now been setup in Zimbabwe, with a second coming online in Türkiye in the coming weeks.
• Ariana is implementing this new time-efficient and cost-saving technology across all its exploration programmes; further experimental work is already underway in Türkiye.

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Kerim Sener, Managing Director, commented:

"We are incredibly impressed with the results of this trial of the detectORE™ system developed by Portable PPB in Perth, Australia. The system has demonstrated itself to be considerably cheaper and faster than conventional analytical methods, which involve shipping to commercial laboratories, more extensive sample preparation and more complex steps in analysis. Crucially, the results of the detectORE™ analyses correlated extremely well with conventional fire-assay results.

"We are now looking forward to implementing the same system based out of our Ankara office so that we can utilise this methodology for all of our routine gold exploration analysis requirements in our South-East European area of operations. Our geoscientific team were present on site in Zimbabwe during the initial set-up and trial of the system and is now in the process of implementing a parallel system in Türkiye.

"Ariana is the first company in Zimbabwe and Türkiye to have implemented this game-changing technology. We have again shown that the Company remains a pioneer of the very latest technologies in our exploration programmes. This has had the effect of ensuring our gold discovery cost remains at the internationally low level of around US$11 per ounce. We look forward to continuing to work with Portable PPB to provide field-based feedback to aid the future development of this breakthrough technology."

Summary

Under normal circumstances, gold cannot be measured in geological samples using field portable X-ray Fluorescence ("pXRF") due to its low concentration and the presence of interfering metals (caused by peak overlap). The patented detectORE™ technology was invented by Australia's National Science Agency, CSIRO, and has been exclusively licenced for commercialisation to Portable PPB Pty. Ltd. ("Portable PPB") who were awarded Western Australia Innovator of the Year in 2023 for their work on detectORE™.

The detectORE™ process overcomes the limitations of pXRF by leaching the gold from the sample using a lixiviant ("GLIX-20™") and a Collector Device ("CD"). GLIX-20™ is a powerful lixiviant with good selectivity for gold and allows for a simple and safe process, practical for in-field use. The CD selectively concentrates dissolved gold, enabling measurement by pXRF. Fundamentally, detectORE™ is a sample analysis technique that enables anyone, anywhere, to measure trace concentrations of gold in geological samples using a pXRF.

A feature of the Dokwe deposit is the amount and extent of pyrite mineralisation in the metavolcanic rocks, irrespective of gold content. This makes the discrimination of gold-rich samples visually difficult, and this has historically resulted in excessive sampling for fire assay, which is expensive and time-consuming. Finding a technique that can point towards gold mineralisation could significantly reduce the number of samples sent for fire assay, and therefore reduce the cost.

Ariana set up a detectORE™ laboratory at the Dokwe Project, and identified samples of a range of gold grades from historic core, on which to test the detectORE™ system and gain an understanding of the relationship between the representative units obtained through the detectORETM process and laboratory fire assay results. Following this, the due diligence drill-core was analysed using detectORE™.

A representative selection of the due diligence/detectORE™ samples was sent to Antech Laboratory (ISO Accredited) in KweKwe, Zimbabwe to be analysed for gold by fire assay.

detectORE™ Method

Intervals to be sampled were selected, and cut in half using a diamond core saw. The swarf (sediment normally disposed of and not assayed) obtained during this cutting was collected and left to settle out from the water used during the cutting process. After each sample, all equipment was carefully cleaned. Once settled, the samples were hung to dry in close-weave calico sample bags to prevent any loss of fines.

Once dry, a pXRF reading was taken from the swarf to obtain multi-element geochemistry. Next, a 250g sub-sample was weighed and placed into a plastic pouch with 500ml of reagent added and a collector device (CD) attached to the inside of the cap of the pouch. The pouches were placed in a barrel and tumbled for 12 hours. After this, the pouches were removed from the drum and CDs were removed from the pouches, rinsed gently in water and dried in a dehydrator oven for three hours (Figure 1).

Figure 1: Photos of the detectORE™ method, from top left to bottom right: Barcode scanning, sample weighing, CD attachment, reagent preparation, adding reagent to sample, loading mixer, mixer running for 12 hours, gently washing CD's, drying CD's, XRF of CD's.

Each batch of 90 samples contained two reference materials supplied by Portable PPB which were processed and analysed in the same way as the core pulp samples. The reference materials are not certified but have known concentrations of gold. They are used to check that the leach and collection process has worked as intended for that batch. In addition, two blanks and two field duplicates were included in every 90 samples.

All samples and sample information are tracked using the bar codes on the pouches and the CD's. The sample numbers are entered into proprietary pLIMSTM software, Portable PPB's software interface for sample management and results. The barcodes prevent manual errors in data entry.

The pXRF detectORETM mode is firmware installed on portable XRF devices to allow detection of gold values from the CD's, controlled via API coupled to pLIMS™ software that also manages the QA/QC. The pXRF detectORETM mode is calibrated using five Calibrated Collector Devices of varying concentrations of gold from 0 to 1,000ppb equivalent. Once dried, the CDs were analysed for gold using Evident's detectORETM mode on a Vanta M Series (VMR) pXRF.

The gold concentration is calculated based on the weight of the original sample and moisture content, and the amount of gold on the CD (i.e., gold leached into solution). The gold concentration is given as dU (detectORETM units), where a dU represents the leached and collected gold in micrograms of gold. This is a partial extraction, not a total gold result. The laboratory results from the trial batches are compared to the detectORETM results, and a correlation coefficient is established. This equation is used to predict the ppm (g/t) values the dU correlates with, and thus help define samples to be analysed at a laboratory using conventional assay. The detectORE™ results when compared to fire assays also provide detailed geometallurgical insights and leach characteristics, further adding value to this process.

As a check for the detectORE™ process, one batch of samples was analysed twice, showing strong repeatability of results.

Initial Results

In total, 1,067 samples (including 106 QA/QC samples) were processed through the detectORE™ system from April to June 2024, of which 79 samples were from historic drill-holes, and 988 samples were from the Due Diligence drilling.

The detectORE™ results showed a strong correlation with fire assay results across a range of grades, from barren to 35.0g/t Au, as seen in Figure 2. It is clear that the detectORE™ results are strongly representative of the fire assay results, despite results being given in detectORE™ units (dU), with mineralised intervals indicated at the same depths and with similar concentrations for both analytical methods.

Figure 2: Section view of due diligence drill holes at Dokwe North (DPD129 and DPD131) and Dokwe Central (DPD130). A good correlation can be seen between fire assay results displayed in yellow bars on the left side of the drill strings, and detectORE results in red bars on the right.

Because of the trial, Ariana has concluded that the detectORE™ results can be confidently used to select samples to be sent for fire assay, or to determine the next phase of sampling. By correlating the detectORE™ results with known assay results, the detectORE™ results can be easily converted to ppm (or g/t) values, which are a close prediction of the potential grade to be obtained via fire assay. For the Dokwe project, a grade of 500 dU was noted to be equivalent to approximately 1.00g/t Au.

The correlation between detectORE™ results and fire assays ranged from 0.72 to 0.99 R2, with an average R2 value of 0.81 (Figure 3). The average difference between the predicted grade and the fire assay grade was ±0.3g/t Au, with differences of greater than ±1g/t Au only seen in 2% of the samples to date (19 samples), 63% of which were greater than 2.5g/t Au in fire assay.

Figure 3: Scatter Plot showing a good correlation between the fire assay results (X-axis) and results predicted by the detectORE method (Y-axis). The graph focuses on the due diligence drilling at Dokwe North (DPD129) and Dokwe Central (DPD131).

Next Phase

In the initial phase, over half of the samples were analysed at the laboratory in addition to all samples being analysed through the detectORE™ process. This is to ensure a better understanding between laboratory results in ppm and detectORE™ results in dU. In future sampling programmes, approximately only 10% of samples would likely be shipped from the project to undergo standard fire-assay or equivalent analysis in a commercial laboratory.

The detectORE™ collectors also capture silver (Ag) and copper (Cu). However, further work is progressing to optimise and understand how Ag and Cu leach and are collected during the detectORE™ process. Silver is both a commodity and gold pathfinder element so having the ability to gain data on silver, in the field, at low concentrations is expected to help find gold and to know when laboratory silver assays are warranted so the value of this metal can be factored into project NPV and mine scheduling. All CD's are being archived safely for future silver and copper measurements after the process has been fully calibrated by Portable PPB.

This trial focused on the use of detectORE™ to analyse drill-core samples. Future work will include analysing soil and stream sediment samples, where the economic and efficiency benefits from near-daily turnaround of analytical results will come into play. Exploration depends on assays to move the process forward to the next stage with confidence. Having near daily gold assays anywhere, using a simple highly mobile process will undoubtedly enable us to explore faster and more confidently and should see further declines in what are already industry-leading low discovery costs, whilst also fast-tracking mine development through better insights into ore leach characteristics.

Editors' Note:

The information that relates to Exploration Results is based upon information compiled by Ruth Bektas, Exploration Group Leader, Ariana Resources plc. Ruth Bektas is a member of Recognised Professional Organisations as defined by JORC 2012: a Chartered Geologist (CGeol, Geological Society of London) and European Geologist (EurGeol, European Federation of Geologists) and has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity upon which she is reporting as a Competent Person as defined in the 2012 Edition of "The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves." Ms. Bektas consents to the inclusion in this report of the matters based on the information compiled by her, in the form and context in which it appears.