The contract includes procurement and commissioning and was concluded after encouraging metallurgical test work in the third quarter of this year.
Mining at Macy started in July and ore is currently being mined above the resource grade of 18.3% zinc.
Macy is part of the Imperial Project, a joint venture with Goidel Resources (40%), a group that has been operating in Nigeria for more than 20 years.
The majority of the plant has been constructed and mobilisation of key equipment will occur in December, with commissioning expected to be completed in the first quarter of 2019.
The 40-tonne-per-hour plant will complement Macy’s existing processing plant to capture additional tonnage from rejected lower-grade material (less than 10% zinc) and is expected to enhance the economics and flexibility of the project.
The favourable metallurgy leading to the decision comprised a low-grade zinc sample of 8.1% being tested and returning concentrate grades of 53.4% zinc and 3.5% lead, with 78% recovery of all contained metal.
The results indicated that Macy’s ore was highly amenable to gravity separation with high metal recovery, producing a high-grade zinc concentrate from coarse feed size.
This eliminates the requirement for a capital-intensive grinding and flotation circuit.