Ann: Quarterly Activities Report & 5B to 31 March 2018, page-10

Metallurgical test work has been conducted at the Mines and Geoscience Bureau (MGB) and Intertek in Manila, Philippines in order to determine the most appropriate method to recover gold and silver from the ore. The work has been conducted under the direction and guidance of Bluebird’s Metallurgical Manager, Peter Wallwin, who has over 40 years of experience of project development.
Initial diagnostic test work indicates that the ore sample tested may be amenable to gravity separation, a simple and low-cost technique for the separation of minerals based on their specific gravity by their relative movement in response to the force of gravity. Further investigations are well advanced to this end.
Leaching test work performed on the ore sample indicated recoveries in excess of 90% of the gold (up to 97% has been reported from some tests) at low reagent consumption. Leaching is a widely used extractive metallurgy technique which converts metals (in this case gold), into soluble salts in an aqueous media. The dissolved metals are then recovered from the solution.
These excellent results from the samples evaluated to date indicate that the ore is not problematic and does not require complicated or expensive extraction techniques. These results will allow the company to commence financial evaluation of different options for the design and construction of its process plant. Recoveries in excess of 90% are considered high by industry standards. Each option will have a capital cost which can be weighed up against operating cost and cash flow.
Further test work is in progress to further evaluate gravity separation as well as some alternative processes. A second, separate set of samples will be taken at a later date from other areas of the mine to verify the results obtained from the initial samples evaluated.
Metallurgical test work is a critical factor in determining the viability and economics of any ore as well for ongoing operations. An ore deposit even of high grade may be compromised should the metal or mineral prove difficult or costly to extract.
The Company is also pleased to announce that the assay results have been received from the recent Kochang underground sampling program. These results are being evaluated and the Company expects to update the market next week.
Colin Patterson, CEO, commented:
“We are delighted with these initial results and the general progress to date at Gubong. The initial metallurgical results are very encouraging and give us the confidence to start looking at the various options available to take the Gubong project to the next stage. We look forward to providing further updates on our progress at both our Gubong and Kochang projects in the near future.”