Gold Recovery Methods at Wapolu Project: Flotation and CIL

Source: Adyton Resources Corporation (2026)
Website: https://adytonresources.com/

Critical Data

Overview

The Wapolu Gold Project, located on Fergusson Island in Papua New Guinea, is advancing under the stewardship of Adyton Resources Corporation. A recent NI 43-101 Technical Report (effective 12 December 2025) details the proposed gold recovery methods for this project. Recent metallurgical testing indicates that a conventional flowsheet consisting of crushing, grinding, and flotation is adequate to produce a high-grade gold-rich concentrate, which could be sold directly to traders or end users. The historic plant, which operated in the mid-1990s, employed carbon-in-pulp (CIP) and cyanide vat leach technologies targeting an overall gold recovery of 80%—a target that was not achieved in practice. The current recovery strategy addresses the unrecovered gold in flotation tailings by considering the addition of a carbon-in-leach (CIL) circuit, should it prove economically justifiable. This two-stage approach (flotation for primary recovery and CIL as a scavenger) aims to maximize overall gold extraction while leveraging marketability of a concentrate product. Before any development decision is made, the company will complete further metallurgical testwork to confirm process parameters, recoveries, and economic viability. These gold recovery methods are central to the project’s feasibility, balancing conventional technology with modern optimization to unlock the value of the Wapolu deposit on Fergusson Island.

Key Process Stages

• Stage 1: Crushing – Run-of-mine ore is reduced through a conventional multi-stage crushing circuit (primary jaw crusher, secondary and tertiary cone crushers) to achieve a product size suitable for grinding. The specific crusher settings and reduction ratios will be finalized following ongoing metallurgical testwork.
• Stage 2: Grinding – Crushed ore is fed to a ball mill (or SAG/ball mill combination) to achieve the target grind size necessary for liberation of gold-bearing minerals. Grinding media type and mill speed are optimized based on ore hardness and desired particle size distribution, with further testwork determining the final specification.
• Stage 3: Flotation – The ground slurry undergoes conventional flotation using a series of rougher, scavenger, and cleaner cells. Reagent additions (collectors, frothers, modifiers) are tailored to the ore mineralogy to produce a gold-rich concentrate. The flotation circuit is designed to maximize recovery of gold and associated sulfides while minimizing dilution.
• Stage 4: Concentrate Handling and Offtake – The flotation concentrate is thickened, filtered, and stockpiled for direct sale to gold traders or smelters. Alternatively, the concentrate may be trucked to a port for export, offering revenue generation without requiring on-site cyanidation of the full ore feed.
• Stage 5: Tailings Treatment with CIL Circuit – Flotation tailings, containing residual gold, may be directed to a carbon-in-leach (CIL) circuit if economically justified. The CIL circuit uses cyanide leaching and activated carbon adsorption to recover additional gold, improving overall plant recovery. The decision to include CIL depends on head grade, gold price, and operating cost analysis from future testwork.

Additional Interesting Data and Summary

The Wapolu Gold Project’s recovery methods section highlights the transition from a historically underperforming CIP/cyanide vat leach plant to a modern, flexible flowsheet. Although the Section 17 content is limited in technical and environmental specifics, it clearly sets the stage for a comprehensive prefeasibility study. The proposed use of conventional crushing, grinding, and flotation is well-suited for the deposit’s mineralogy and offers the advantage of producing a saleable gold concentrate, reducing onsite cyanide usage compared to whole-ore leaching. The optional CIL circuit for tailings provides an insurance mechanism to boost overall gold recovery if economically viable. From an economic perspective, direct concentrate sales can lower capital and operating costs by eliminating the need for a complete on-site refinery. Environmentally, the chosen methods allow for better tailings management through conventional thickening and filtration. Sustainability initiatives are implied by the focus on maximizing recovery without excessive reagent consumption. The project’s future outlook depends heavily on the upcoming metallurgical testwork program, which will confirm key parameters such as grind size, flotation residence time, reagent dosages, and cyanide consumption. This testwork is critical for de-risking the process design and securing financing. The historical failure to achieve 80% recovery underscores the importance of thorough geometallurgical characterization before finalizing the process flowsheet. The technical report, dated 7 January 2026, emphasizes that no development decision will be made without further testwork, demonstrating a disciplined approach to project advancement. Once completed, the Wapolu Gold Project could become a significant gold producer in Papua New Guinea, leveraging conventional recovery methods tailored to local ore characteristics.

Key Processes: Flotation, CIP/CIL, Cyanidation, Crushing

Target Commodities: Gold