During the Quarter ended 31 March 2022, the Company completed its Phase II RC drilling program at the 100%-owned Burracoppin Gold Project located in the eastern wheatbelt of Western Australia in close proximity to the Edna May Gold Mine owned by Ramelius Resources Limited (ASX: RMS).
The Burracoppin Project is located approximately 20km east of Merredin and 15km west of the Edna May Gold Mine in the eastern wheat belt of WA.
Phase II RC Drilling Campaign
During the Quarter ended 31 March 2022, the Company drilled a total of 12 holes for approximately 1,300m as part of the Phase II RC drilling campaign. The Phase II program was designed using historical drill data, the Company’s Phase I drill results and the new magnetic data. A third phase of RC drilling is planned to commence in the second quarter of 2022 and will be testing additional targets along strike and on parallel structures as well as infill holes where required. The design of the second phase focused on an area west of the Benbur historical mine and below an area previously mined by a shallow oxide mine. Phase one drill results from the Company’s inaugural drilling campaign intersected high-grade results at depth, which warranted further follow up.
These results include 4m @ 4.27 g/t Au from 25m in ABRC010, including 2m @ 7.88 g/t Au from 25m, as well as 2m @ 2.38 g/t Au from 22m in ABRC013. The area also includes several physical characteristics that provides additional weight to its mineralisation potential and scalability of the area. One such feature is that the mineralisation is associated with a ridge that follows the structural orientation as indicated by the high definition magnetic survey completed by the Company. Mineralising fluids passing through the structures often alter the host rock, increasing its resistance to weathering and resulting in a topographic anomaly. The Company believes the association of the mineralised intersections with the topographic anomaly is a reason for further testing.
The map below illustrates the location of the drill holes for the Phase II RC drilling campaign at the Burracoppin Gold Project. The Phase II drill hole collar locations are highlighted along with the results intersected during the Phase I drilling program.
The Phase III program will test strike extensions and parallel structures as highlighted by the areas in the yellow outline of Figure 3 (below), being Burgess Find, Easter Gift, Lone Tree, Benbur (strike extensions) and Christmas Gift.
Phase II RC Drilling Campaign: Discussion of Results
The Phase II RC drilling program was completed in late February 2022 and comprised 13 holes for 1,300m. This second drill program was designed using historical drill data, Phase I drill results and the new detailed magnetic data acquired by the Company.
The design of the second phase focused on an area west of the Benbur historical mine and below the previously mined area of laterite hosted shallow gold oxide material. Phase I drill results from the Company’s inaugural drilling campaign intersected high-grade results at depth. These results include 4m @ 4.27 g/t Au from 25m in ABRC010, including 2m @ 7.88 g/t Au from 25m, as well as 2m @ 2.38 g/t Au from 22m in ABRC013.
The area also includes several physical characteristics that provide additional weight to its mineralisation potential and scalability. One such feature is that the mineralisation is associated with a ridge that follows the structural orientation as indicated by the high definition magnetic survey.
Twelve holes were drilled along 200m of strike west of the Benbur mine, testing an area below a historical cyanide leach pad. The design was formulated after two Phase I drill holes targeting potential mineralisation interpreted from 5m deep RAB holes beneath an old leach pad, returned very positive results, including 4m at 4.27 g/t Au from 25m in ABRC010 (see AS2 ASX Announcement dated 14 October 2021).
The Phase II program tested strike extensions north and south beyond the leach pad and tested for depth extensions. Figure 4 below depicts a plan view of the drill program.
Mineralisation beneath the central portion of the leach pad was tested by a fence of three holes drilled below each other. Hole ABRC027 is the deepest of a three-hole stack targeting the central part of the leach pad. It was collared furthest east and drilled through the Benbur workings a few meters south of the shafts to reach its target.
It intersected mineralisation associated with the Benbur workings (including a 1m wide void) and encountered 8.5m at 4.88 g/t from 19.5m. It also continued to intersect its design target at depth and returned two deeper intercepts of 2m at 1.2 g/t Au from 46m and 2m at 2.15 g/t Au from 111m downhole. Figure 6 depicts section “B” (refer to Figure 4) through the three-hole stack, including holes ABRC027, ABRC028 and ABRC029.
On section (refer to Figure 6, below), it appears likely that extending ABRC027 may result in the intersection of a fourth zone of mineralisation. As part of the third phase of RC drilling, ABRC027 will be re-entered and drilled deeper to intersect the fourth zone of mineralisation.
The continuation of mineralisation along strike to the north was tested and confirmed by another line of three holes drilled below the other. The three-hole stack consists of holes ABRC022, ABRC023, and ABRC024, as well as hole ABRC021 drilled along strike and to the north.
Figure 5 depicts section “A” through this stack and shows the intercepts achieved by the second phase of drilling and the interpreted mineralisation model through the area. The Company is pleased that the drilling identified a continuation of the mineralised strike of this new and western zone of mineralisation and plans to test the extension of both this zone and the main parallel zone to the east with future drill programs. The third phase of drilling is scheduled to commence in late May 2022.
The Burracoppin Gold Project has been drill tested by explorers prior to the exploration work completed by the Company, however, the drill data has never been combined into a coherent mineralisation model. After completing two drill phases comprising 29 drill holes in addition to the historic drilling, the Company engaged an independent geological consulting company to construct a mineralisation model of the current dataset. The data is not comprehensive in all areas, and so the model aims to provide a 3D interpretation of the various gold intercepts using the Company’s interpretation of the characteristics of the mineralisation based on surface mapping, structural interpretation of the HD magnetic survey completed over the project, historic drill intercepts and historical maps.
The completed mineralisation model focussed on the area around the Benbur historic workings because this area contains the bulk of the drill data. The model will be extended further along strike as the drill intercepts from AS2 drill campaigns continue. The mineralisation model identified several sub-parallel units beneath the old leach pad and identified similar units to the east beneath the area mined by the Benbur mine.
This 3D model will be concept tested by future drill campaigns but will allow the Company to design drill targets based on a 3D model, which has never been possible before. The model will be reinterpreted with the new data from each future drill campaign, therefore becoming more robust as work continues.
Eight of the twelve drill holes returned intercepts of greater than 1 g/t Au over at least 1m with hole ABRC028, for example, returning 1m @ 13.2 g/t Au from 34m. The table of significant intercepts is shown below. Table 2 below shows the intercepts greater than 1g/t Au as well as the samples in their immediate vicinity.
Table 2: Table of the main intercepts greater than 1 g/t Au as well as the surrounding results in each hole.
Soil / Lag Sampling Campaign
During the Quarter ended 31 March 2022, the Company completed a review of the historical surface sample data on the Burracoppin Gold Project, revealing certain individual anomalies that correlate well with the Company’s interpreted extension of the mineralised envelope on the Project. The anomalous samples also connect well with interpreted mineralisation extension for the area recently tested by the Company’s second phase of RC drilling, west of the Benbur historical working. The surface sampling program was designed to validate the historical anomalous samples and test for the potential extension of the mineralised enveloped as per the Company’s interpreted model for the project.
Seventy-two (72) samples were collected during this phase of exploration. The Company is delighted by the results received from the exploration campaign as it has not only validated the historical data set but also confirmed the Company’s interpreted mineralisation envelope by increasing the strike extent beyond the historical Benbur workings to 1.1km. The overall potential mineralised strike extent at Burracoppin has now been confirmed at three separate sites representing three separate mineralised zones over a combined strike of 3km. A total of 69% of the samples returned anomalous gold results greater than 20 ppb Au, while 21% returned results greater than 100ppb Au. One result was as high as 2 g/t Au.
The Company is very pleased that the results validate the historical data by appropriately duplicating the historically anomalous samples. The recent results, in combination with the now validated historical results, also indicate a 1.1km long anomalous gold trend at the surface, which correlates well with the Company’s interpretation of the mineralisation in this area of the Project. The mineralisation trend also presents a target to be tested by drilling in the coming months, as part of the Phase III RC drilling program.
Previous explorers on the Burracoppin Gold Project conducted surface sampling over certain areas within the licence. Evaluating these results by the Company identified areas that warranted follow up to determine their mineralisation potential. The first step was to validate the historical results with fresh samples as well as include several infill samples designed to test for mineralisation extension. A lateritic pisoid Lag covers the sampled area, so traditional soil samples could not be used. Instead of using mechanical methods to collect the samples, the Company collected 72 Lag samples from a depth of about 20cm.
NOTE: Lag is a general term applied to coarse-grained (> 2 mm), hard but partially weathered rock fragments concentrated at the surface through the attrition of finer materials.
Several samples were designed to twin historical results to validate the anomalous historical gold sample results accurately. At the same time, several other samples were designed and collected to test the strike extension of the anomalous mineralisation. The design of the samples testing the mineralisation extension was influenced by the high definition magnetic survey the Company completed on the project as well as historic and Company underground drill intercepts. Samples were in the form of Lag samples collected by hand from a depth of 20cm and sent to the laboratory for assay. Figure 7 indicates sample locations.
Discussion of results
Fifty samples (69%) out of seventy-two samples collected were anomalous with gold results of greater than 20ppb Au. Fifteen samples were very anomalous, returning results greater than 100ppb Au and validating the interpreted strike extension of the projected mineralised envelope. One sample returned a result of 2g/t Au, demonstrating a real potential for high-grade mineralisation in the area.
Figure 8 depicts the location of the recent soil sample results as well as the gridded results of the combined historical and recent results.
The Company is delighted with a high strike rate of 61% of the samples collected being anomalous above 20ppb Au and believe that this validates the historic gold anomalies in those same areas. Mineralised trends are clearly visible when combining the recent data with the historical data set. One interpreted mineralised trend continues north beyond the extent of the area recently tested by the second phase of RC drilling completed by the Company. This is very encouraging and suggests the potential extension of mineralisation even further north along strike. A second mineralised zone is also made evident, which correlates well with the zones targeted by the historical workings of Benbur. These results validate the Company’s interpretation that the project may have several parallel or sub-parallel mineralised structures.
The extent of surface mineralisation around the known historical workings of Benbur in the south and Burgess Find in the north is now just over one kilometre. It is essential to note that a significant proportion of this proposed mineralised strike length remains untested by drilling beyond 5m depth and that the Company intends to test these during the course of its future exploration activities on the project. Figure 9 depicts the interpreted mineralised zones resulting from examining and interpreting the combined surface sample data.
Auger Sampling Campaign
The soil auger program was designed to test several targets along the strike extent of the interpreted Burracoppin gold mineralisation. Some lines of auger samples test the strike extension of the primary northern mineralisation around the Benbur (south) and Burgess Find (north) workings. Several lines of auger samples also test the central and southern portions of the project, testing areas of known mineralisation and their strike extent as well as testing new areas identified from historical data review. The high definition magnetic survey also allowed for the interpretation of several targets, which are also tested by this auger program. Finally, the current soil auger work tests a very exciting surface anomaly, highlighted by the historical data review east of the Benbur workings.
New Mineralisation potential
Historical surface soil samples indicate a potential untested zone of mineralisation east of the Benbur workings. The current auger program is designed to test this area. If successful, it will unlock a completely untested zone of mineralisation below the surface and thereby also add significant potential to the project.
Figure 11 depicts the interpreted mineralised east of the Benbur historic workings.