Name of the Project
Palmer zinc/copper/silver/gold project.
Location
The project is located in south-east Alaska, in the US.
Project Owner/s
Constantine Mining LLLC Joint venture, in which Constantine Mineral Resources owns a 51% interest.
Project Description
A preliminary economic assessment (PEA) has demonstrated a high-quality project, with strong economics and a progressive, environmentally conscious mine design.
The project has total indicated resources of 4.6-billion tonnes grading 5.23% zinc, 1.49% copper, 30.8 g/t silver. 0.30 g/t gold and 23.9% barite.
Zinc equivalent is estimated at 10.21%.
Inferred resources are estimated at 9.59-billion tonnes grading 4.95%, 0.59% copper, 0.43% lead, 69.3 g/t silver, 0.39 g/t gold and 27.7% barite.
Zinc equivalent is estimated 8.87%.
The PEA proposes the concurrent mining of the Palmer and AG Zone deposits.
Initial material from the Palmer deposit will be recovered at 2 700 t/d by underground longhole stoping mining methods.
During the third year, production will start at the AG Zone deposit and increase total production to about 3 500 t/d.
The project incorporates a standard 3 500 t/d comminution and a flotation separation flowsheet, including a primary underground crusher feeding a semiautogenous mill three-stage flotation to produce copper,
zinc and barite concentrates for shipment to off-site smelters.
A fourth concentrate, pyrite, will also be produced for placement underground as paste backfill.
The project is expected to have a mine life of 11 years.
Life-of-mine recovered metal production is estimated at 1.07-billion pounds of zinc, 196-million pounds of copper, 18-million ounces of silver, 91 000 ounces of gold and 2.89-million tonnes of barium sulphate.
Potential Job Creation
Not stated.
Net Present Value/Internal Rate of Return
The project has a pretax net present value, at a 7% discount rate, of $354-million and an internal rate of return of 21%, with an after-tax payback period of 3.3 years.
Capital Expenditure
Preproduction development capital is estimated at $278-million.
Planned Start/End Date
Not stated.
Latest Developments
The Palmer and AG Zone deposits are open at depth.
The potential exists to discover additional zones within the Palmer district.
The PEA has recommended preliminary metallurgical testwork on the AZ Zone deposit to assess the potential to enhance metal recoveries and grade, particularly for silver.
The PEA has further suggested future trade-off studies for offsite infrastructure such as an ore terminal in Haines or expanded hydropower capacity within the local grid.
Key Contracts and Suppliers
JDS Energy and Mining (PEA); Klohn Crippen Berger (water and waste management design components, and processing plant site foundation assessment).
On Budget and on Time?
Not stated.
Contact Details for Project Information
Constantine Mineral Resources, tel +1604629 2348 or email info@constantinemetals.com.