Buccaneer Gold Deposit
Overview
The Buccaneer Gold Deposit is part of the Tanami West Project which is one of the key developmental projects for Prodigy Gold. It is classified as an intrusive hosted gold deposit and is currently the only such type of deposit defined in the Tanami region to date.
The Buccaneer Deposit is located on ML29822, 5.5km to the northwest of the Old Pirate Mine and 27km to the south of the Tanami Road.
Buccaneer hosts a total 2023 Mineral Resource (including Indicated and Inferred categories) of 9.2Mt @ 1.2g/t Au for 359Koz¹ using a lower cut-off grade of 0.6g/t Au.
This updated estimate represented an overall decrease in the number of ounces previously reported for the deposit. This was a result of the new Mineral Resource having been calculated within an optimised pit shell. The underlying resource(including material outside of this shell) was very close to the previous resource estimate from 2017.
Several studies have been completed on the deposit, such as metallurgical andgeo technical reports, to assist with the development of a more detailed mining study when required.
¹ASX: 11 August 2023
Buccaneer Exploration History
The Buccaneer Deposit was originally discovered by North Flinders Mines in the late 1990s. Newmont Asia Pacific Ltd (Newmont) acquired the tenement and continued active exploration through 2006. Newmont/North Flinders drilled a total of 830 holes into the Project – 103 AC, 669 RAB, 48 RC, and 10 RC with diamond extensions – totaling 51,082m, and provided the foundation to understanding the geology and structural make-up of the Buccaneer Deposit.
Significant historic RAB drilling covers the area and was used in developing the lithological and mineralisation interpretation. 124 AC, 163 RC, 8 RC(D) with diamond tails and 5 diamond holes were drilled between 1993 and 2015 and was undertaken by several companies:
- 1993– 1996: RAB and DDH drilling by North Flinders Mines
- 1997 – 1999: RC and RAB drilling by North Flinders Mines
- 2004: AC, RAB and RC drilling by North Flinders Mines
- 2010 – 2015: AC, RC, RCD and DD by Prodigy Gold
- 2020 – 2023: AC and DD by Prodigy Gold.
Buccaneer Mineral Resources
The Buccaneer Mineral Resource update incorporates results from the 2020 and 2021 Buccaneer drilling campaigns. The estimation was completed considering only open pit mining methods.
The Buccaneer Mineral Resource was reported constrained within an optimised open pit shell calculated using a gold price of A$2,960/oz, mining, processing and G&A costs of $56/ore tonne and pit wall angles from completed geotechnical studies. The mineralisation continues past this level and is being used to assist the planning of future deeper drilling.
The 2023 Buccaneer Mineral Resource update totals 9.2Mt at 1.2g/t Au for a total of 359koz of gold¹ and has been reported in the Indicated and Inferred categories. Recent studies on the metallurgical recoveries for the deposit have also been reviewed, highlighting that this deposit would be suitable for processing through a conventional carbon-in-leach (“CIL”) processing facility with estimated recoveries of over 95.1% in oxide, 96.7% in transitional material and 84.6% for fresh material based on the metallurgical testwork results from IMO completed in 2023².
¹ASX: 11 August 2023, ²ASX: 10 March 2023
Buccaneer Geology and Mineralisation
The Buccaneer intrusion is interpreted to be a multi-phase syeno-monzogranite intrusion. The intrusion is dominantly composed of plagioclase and K-feldspar with lesser quartz and biotite hosted within a fine grained but equigranular groundmass. Most of the deposit has been drilled with RC, however, it is postulated that two phases of intrusion are recognisable in diamond drill core.
- The Phase 1 high-K quartz-monzonite has a higher proportion of K-feldspar, a lower proportion of plagioclase and a reddish to pink hue.
- The Phase 2 quartz monzonite is a high-Ca end member of the quartz monzonite. The high-Ca end member has a relatively higher proportion of plagioclase and a lower proportion of Kfeldspar.
In early 2010, several RC holes scanned for multi-spectral analysis by a portable infra-red mineral analyser (“PIMA”) showed the Buccaneer intrusion to be highly enriched in bismuth, molybdenum, tungsten and copper.
A locally intense texturally destructive sericite alteration is found in both intrusive types. This alteration appears to be structurally controlled and is largely associated with shearing.
Mineralisation extends from near-surface to a depth of over 500m and has been defined in several zones over an area of 2,300m by 800m. Gold mineralisation is disseminated throughout the monzogranite with higher grade zones typically associated with zones of shallow dipping quartz veins as well as sulphides (pyrite, arsenopyrite), although free gold is also seen in the quartz stockwork veining.
Buccaneer MBuccaneer Deposit Development Potentialineral Resources
The Buccaneer Deposit has potential for future development using an open pit methodology based on the results of studies completed over the last few years. The Buccaneer Mineral Resource highlights the scale potential of the deposit located on an active Mineral Lease.
The studies completed on an 8-hole diamond drilling program, completed at the end of 2021 include the metallurgical testwork program completed by IMO in 2023 and the geotechnical study competed by Peter O’Bryan and Associates in 2022. The results of these studies include:
- Metallurgical – Gravity gold and cyanide leach testwork returned recoveries of 95.1%, 96.7% and 84.6% for the oxide, transition and fresh composites, respectively with gravity gold recoveries averaging 18.6%. Fastest kinetics were achieved for the oxide and transition composites. Low cyanide and lime consumption was noted for each of the oxide, transition and fresh composites¹.
- Geotechnical – recommended wall angles were 55o to 380mRL with 5m berm, 60o to 335mRL with 6m berm and 65o below 335mRL with 7m berms.
These results were used in the pit optimisation work completed on the updated Mineral Resource in 2023.
¹ASX: 10 March 2023