Tietto Minerals Ltd (ASX:TIE) has confirmed significant metallurgical recoveries from heap leach test work of lower‐grade halo mineralisation at the APG deposit, part of the company’s 3.45Moz Abujar Gold Project in Côte d’Ivoire, West Africa.
Testing was completed on 140 kilograms of diamond core samples drilled at APG representing low‐grade ‘halo’ material, with head grades ranging from 0.16 g/t Au to 0.54 g/t Au.
Test work results show:
- Moderate crush size of 12.5 millimetres – crush size not optimised and coarser crushing is likely for field operations with lower operating costs
- Moderate cement additions (12kg/t) for oxide and transitional material. Cement dosage for the more competent fresh material (2kg/t) was more for pH control than permeability
- Low cyanide consumption (0.24‐0.67kg/t) for oxide & transitional to fresh respectively
- Rapid gold leaching for oxide columns with more than 80% achieved by Day 10 and up to 95% final extractions. Fresh column reported 50% extraction by Day 7 and 82% final extraction
- Good permeability and low slump levels
Column test recovery curves.
Importantly, test results demonstrate heap leaching can be used on APG’s lower grade material which is not able to be economically processed at the Abujar mill, with the potential to unlock further value from the project.
Tietto managing director Dr Caigen Wang said: “Results of this latest test work program confirm the amenability of APG oxide, transitional and fresh material to heap leach processing.
“This has the potential to extract additional value for shareholders from the considerable amount of low‐grade halo material at APG which is currently uneconomic to process using the 4.5Mtpa Abujar Mill being built 7km to the north of APG.
Abujar oblique view showing the location of deposits and prospects making up the Abujar resource.
“We asked the engineers to run a scoping study work to quantify the economic benefits of an additional heap leach operation that could run in parallel with the 4.5Mtpa CIL processing path.
“This scoping study will be incorporated into an update of Abujar’s LOM production plan using the latest Mineral Resource, higher spot gold prices and increased Abujar CIL mill throughput (4.5Mpta ‐ fresh ore)."
Next steps
Tietto announced a A$130 million two‐tranche placement on 29 March 2022 to accelerate the development of Abujar, with no debt.
The placement allowed the participation of like‐minded investors, keen for the company to realise first gold production by Q4 CY22 and produce 260,000oz gold in 2023.
Tietto remains well-positioned to advance its dual strategy of ‘Drill and Build’ into 2022:
- Continue to drive rapid resource growth at the 3.45Moz Abujar Gold Project; and
- Fast‐track development of Abujar Gold Project to achieve first gold in Q4 CY22.
West Africa’s next producing gold mine
The company continues to deliver project milestones; with Abujar’s maiden measured gold resources of 7.7 million tonnes at 1.4 g/t gold for 350,000oz reported on 11 April 2022.
Tietto will deliver an update on Abujar’s LOM production plan by the end of Q2 CY22 using the updated resource estimate, increased mill throughput and higher gold prices (spot price is +35% greater than US$1407/oz used in the DFS), targeting a material increase to existing LOM production.
The company is advancing the construction of the process plant and associated infrastructure which remains on schedule.
Abujar Gold Project is progressing towards first gold pour by the end of Q4 CY22 and is on track to become West Africa’s next producing gold mine.
260,000+ ounces of gold expected in the first year
Wang added: “We are fully funded to production at Abujar, which has potential to be one of the largest gold producing mines in Côte d’Ivoire, with an expected production of more than 260,000 ounces of gold in the first year and 1.2M ounces of gold in the first six years.
“Tietto has an experienced team on board to deliver Abujar on time and on budget.
“We are on track to deliver another mineral resource update and first gold at Abujar later this year.
“Shareholders can expect further updates from our aggressive diamond drilling program as we advance our dual strategy of ‘Drill and Build’ and develop the Abujar Gold Project into West Africa’s next gold mine with first gold by the end of Q4 CY22.”