Name of the Project
Simberi sulphides expansion.

Location
Simberi Island, in the province of New Ireland, Papua New Guinea.

Project Owner/s
Gold miner St Barbara.

Project Description
The ten-year mine plan at Simberi includes the mining of several openpits to exploit the substantial oxide and sulphide ore reserves. 

The concept study envisages production of two-million ounces of gold.

The study considers six different cases, comprising two flowsheet options with three different processing rates – two-million tonnes a year, three-million tonnes a year and 3.7-million tonnes a year. 

The two flowsheet options propose:
•    production of a gold concentrate for sale; and 
•    production of gold doré from ultrafine grinding (UFG) and cyanide leaching of the concentrate.

Investment in the 3.7-million-tonne-a-year saleable concentrate flowsheet provides the most compelling development pathway – lifting Simberi’s production from its current range of 70 000 oz to 75 000 oz across the 2025 to 2027 financial years to an average of 230 000 oz from the 2028 financial year.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
Not stated.

Capital Expenditure
$213-million.

Planned Start/End Date
First sulphide production is expected in the 2028 financial year.

Latest Developments
St Barbara is advancing as “quickly as possible” to bring forward production from the Simberi sulphides expansion.

St Barbara has reported in its quarterly report for the three months ended September 30, 2024, that overall gold recovery for the saleable concentrate flowsheet has improved by about 5% over historical testwork owing to the addition of cleaner scavenger flotation and improved flotation/regrind conditions making this flowsheet a clear choice over the ultrafine grind/cyanidation flowsheet alternative. The metallurgical testwork programme remains on track for completion at the start of the March 2025 quarter.

Tender documents were sent out in September for the planned feasibility study update (Class 3) expected to start in the third quarter of the 2025 financial year.

Key Contracts, Suppliers and Consultants
None stated.

Contact Details for Project Information
St Barbara, tel +61 3 8660 1900 or email info@stbarbara.com.au.