Run-of-mine dump leach material
is placed on the old sulphide ore pad and leached.
The economic study considered a base case mining rate of 20,000 tonnes per day mining 247 million tonnes of leach material
over a life of mine of 36 years averaging 25.
was considering the feasibility of recovering gold from the lower grade, heap leach material
, which contained an estimated 64,000 oz of gold.
Vector Engineering has completed its preliminary infrastructure study for the layout of heap leach pads, dumps and basic infrastructure to support a mining operation producing approximately 150,000 tonnes of copper cathode per year from both heap and dump leach material
Blue represents premium leach material
, pink represents high-grade leach material
, and green represents low-grade leach material
At present the grade of the dump leach material
is too low to justify crushing and heap leaching, but it does contain enough copper to warrant stockpiling as dump leach ore.
The Gossey, Sokadie and Korezeina prospects will also receive additional drilling to evaluate their potential as large sources of lower-grade heap leach material
Production is apportioned into crushed and ROM heap leach material
, based on ore grade, divided roughly 75/25 by tonnage.
One third of this arc is dedicated for mill feed and the remainder is used for heap leach material
Production from the heap leach material
in 2004 is expected to be about 75,000 ounces of gold at an estimated cash cost of $211 per ounce.
Gold production levels at the mine have decreased significantly compared to the corresponding previous quarter due to production shortfalls caused by placing of heap leach material
with slower than expected metal recoveries during the final mining stages.
The year over year sales revenue decrease is due to production shortfalls caused by production interruptions and "placing" of heap leach material
with slower than expected metal recoveries during the final mining stages of the Rawhide operation.