New Liberty Mine In Liberia

Mining method conventional open pit mining at New Liberty mine

New Liberty mine is commercial gold mine in Liberia,  located within the Bea-MDA property, in Grand Cape Mount County in the north-western portion of the Republic of Liberia, approximately 100km north-west of the capital, Monrovia.

New Liberty mine is 100% owned by Aureus Mining inc, through its subsidiary Bear Mountain Mining Corporation,  environmental permit for the New Liberty mine was received in October 2012 and the definitive feasibility study was completed in 2013.

Construction work at New Liberty mine commenced in December 2012 and the first gold was poured in October 2013, while commercial production in New Liberty mine is expected to commence in 2014 and expected annual gold production to be 119,000 ounces (oz) for the first six years and 859,000oz over the mine life of eight and half years.

Mineralisation And Gold Deposit In New Liberty Mine Liberia

Shearing at Gondoja

New Liberty mine is a high-grade ore, Archean, shear-hosted gold deposit with well-defined alteration and sulphide mineralogy. And this mine  is a part of the Bea-MDA property, in the Grand Cape Mount County of Republic of Liberia. The Bea Mountain mining license is spread over 457km2 and also includes the Ndablama, Gondoja and Weaju gold deposits.

The mineralisation is structurally controlled and can be followed for 2km along an easterly strike and has been drilled down to vertical depths of 500m below surface,  and comprise of ultramafic units filled with pyrrhotite and arsenopyrite.

The gold mineralisation is structurally controlled and hosted in a 100m-wide, steeply dipping ultramafic unit surrounded by migmatitic gneisses and amphibolites. 

This is accompanied by bleaching, silicification (but no quartz veins) and phlogopite alteration on the margins. Late pegmatites and aplite veins are present in the hangingwall, footwall and ultramafic host rock and their occurrence is coincident with the mineralisation.

The metamorphic grade of the deposit is lower amphibolite grade. The deposit shows strong magnetic and IP signatures. The gold is fine grained and free – associated with both the sulphides and silicates.

New Liberty has clearly defined high-grade pay shoots which relate to fold and shearing events. Mineralisation at New Liberty is clearly related to shear deformation and sulphidation of a magnetite rich ultramafic unit.

The New Liberty mine is estimated to contain reserves of approximately 924,000 ounces of gold grading 3.4g/t. The measured and indicated resources are estimated to be 1.14moz of gold grading 3.63g/t, whereas the inferred resources are 593,000oz grading 3.2g/t 

The planned open pit will be 2km long and 220m deep and this has a reserve of 8.6Mt at 3.4g/t containing 924koz gold (above a 0.8g/t cutoff). The mine will have an 8 year life and will process 1.1Mt of ore per year.

Mining And Processing At New Liberty Mine In Liberia

New Liberty mine is mining method conventional open pit mining using drill-and-blast, load and haul will be applied at the gold mine. The ore will be loaded onto trucks using hydraulic excavators. Waste rock will be dumped to the dump wrapping around the open pit.

The mineral ore at New Liberty mine in will be processed using two-stage crushing circuit and a primary mill with regrinding. Then the next process stage through ball mill,  which will have a processing capacity of 1.1mtpa of ore per annum.

Gold mineral leaching process in New Liberty mine  usin carbon-in-leach circuit (CIL) and recovered ore with electrowinning. The gravity concentrate will be leached in an intensive leach reactor. Cyanide in the tailings will be detoxified in three stages before discharging to the tailings storage facility.

Commercial production will be declared on the first day of the calendar month following the mill having operated at an average of 60% or more of the designed production capacity, calculated over a 60 day period. Management now expects to achieve commercial production in early January 2016.