This technical report describes the mineral processing and metallurgical testwork for the Gosowong property, including the existing plant flowsheet and historical operating performance.
Report context
This technical report was prepared for Newcrest Mining Limited with an effective date of 31 December 2011, covering the Gosowong property located in North Maluku Province, Indonesia. The report documents mineral resources, mineral reserves, mining methods, and recovery methods for the Gosowong open pit mine, Kencana underground mine, Toguraci underground project, and a tailings reclamation project.
Processing route
Process Plant Flowsheet
The report presents a process plant flowsheet that was designed for gold recovery. The flowsheet incorporates whole ore leaching in a carbon-in-leach circuit.
Plant Performance
The report provides historical plant performance data showing actual outcomes from the operating plant. The plant had achieved a gold recovery rate of 91.5 percent.
Metallurgical Testwork
The report documents metallurgical testwork conducted to support process design. This testwork included comminution testing, leaching testwork, grind size–recovery relationship studies, oxygen uptake measurements, liquid-solid separation testing, and rheology investigations.
Comminution testwork evaluated the grinding characteristics of the ore, including bond work index determinations.
Leaching testwork examined gold extraction under various conditions to establish the relationship between grind size and gold recovery.
Oxygen uptake testing measured the rate of oxygen consumption during leaching to determine oxygen requirements for the leaching circuit.
Liquid-solid separation and rheology testing provided data for thickener and filtration equipment design.
Other investigations included additional metallurgical studies to support process design decisions.
Key reported parameters
| Parameter | Design | Actual Operating | Testwork Basis |
|---|---|---|---|
| Gold recovery | Information not provided | 91.5 percent | Information not provided |
| Comminution characteristics | Information not provided | Information not provided | Bond work index tests conducted |
| Leach kinetics | Information not provided | Information not provided | Grind size–recovery tests; oxygen uptake tests |
| Solid-liquid separation | Information not provided | Information not provided | Thickener and filtration design testwork |
| Rheology | Information not provided | Information not provided | Rheology testwork conducted |
Project website: https://www.mining-technology.com/news/newcrest-finalises-gosowong-sale-indotan/
Technical qualifications
This report does not present a complete flowsheet with all unit operations and equipment specifications. The processing section is limited to the flowsheet overview and one historical recovery value. No secondary processing steps, reagent consumption data, or detailed process control information are provided. The report notes that the plant design was based on metallurgical testwork, but specific design criteria, performance guarantees, and economic parameters are not included in the processing section. The report contains no recent processing data beyond the stated 91.5 percent gold recovery.
Source: Technical Report on the Gosowong Property, effective 31 December 2011, Section 13 Mineral Processing and Metallurgical Testing, Section 17 Recovery Methods.
