May/June 2013 - The ASIA Miner

Philippines
Co-O expansion nears completion
THE expansion work at Medusa Mining’s Co-
O Gold Project is on schedule with the SAG
mill and primary crusher expected to be commissioned
during June following commissioning
of the detoxification plant in April. The
phase 3 expansion will double annual production
from 100,000 ounces of gold to
200,000 ounces.
Mill work completed in recent months includes
conversion and commissioning of leach
tanks from carbon-in-pulp to carbon-in-leach
with six old, small leach tanks removed. The
Construction of the SAG mill at Medusa Mining’s Co-O Gold Project in eastern Mindanao.
thickener upgrade and gold room upgrade
have been completed and these facilities are
in operation while the emergency feed facility
has also been completed.
The main sub-station as well as the mill and
mine transformer stations are completed and
electrified while 42km of electrical wiring at
the new plant is progressing with expected
completion in May. The mine is also being expanded
and by mid-April in the Level 8 development
about 200 metres of horizontal
development measuring 3 x 3 metres had
been completed and 4 veins intersected to
the south of the Saga Shaft, with another 7
veins to be intersected as work progresses.
Development for infrastructure installation is
ongoing and on-vein development is progressing
on the East Agsao 13, 14, 15 and 16
Veins with 7 headings active. By June 30 Medusa
expects about 12 on-vein headings to be
operational and producing development ore.
The winze ore pass from Level 5 to Level 8 is
expected to be connected to the level development
in July. Two Alimak rise ore passes are in
progress from Level 8 to Level 6 and are expected
to be operational in August. Ore from these
passes will be fed by conveyor to the ore bins.
The company has received results from research
conducted by the Centre for Exploration
Targeting, School of Earth and
Environment at The University of Western Australia.
The research involved measurement
of the temperatures of ore formation and salinity
of the ore fluids with the aim to determine
the trends and dimensions of gold
potential in the system.
Results show that there are no apparent
trends to indicate that the margins of the epithermal
gold zone have been reached. They
support the ‘potential exploration target size’
of 3 million ounces in 9.8 million tonnes to 7
million in 23.5 million tonnes.
Agata North project on fast track
AN updated and reclassified resource estimate
for the Agata North nickel laterite resource has
prompted a decision by joint venture partners
Mindoro Resources and TVI Pacific, along with
its Philippines operating subsidiary TVIRD, to
fast-track direct shipping operation (DSO) development.
This is likely to result in production
commencing in late 2013.
Measured and indicated resources have increased
to 33.9 million dry metric tonnes (dmt)
@ 1.1% nickel compared to the previous 31.8
million dmt @ 1.05% nickel. Inferred resources
are 2.0 million dmt @ 1.04% nickel. At a cutoff
grade of 44% iron, there are an estimated
7.9 million dmt or about 10 million wmt @
48.5% iron and 0.94% nickel, a DSO product
grade much in demand in China
The joint venture partners say the new resource
provides a robust foundation for moving
forward, initially, with a DSO of high-iron
limonite (upper laterite horizon), followed by
atmospheric leach processing of the underlying
saprolite horizon. The resource forms
part of an updated NI 43-101 technical report
on the Agata North nickel laterite resource.
The current estimate gives a superior
grade-tonnage distribution to the previous
Agata resource estimate which was carried
out in 2011. Sufficient high-iron limonite has
been defined for approximately 5 years of
DSO production at an annual rate of about 2
million dmt. During this period, it is expected
that the processing plant will be in operation.
TVI has reported to the JV that both the
high-iron DSO and the limestone DSO are
near-term opportunities that have the potential
to generate strong cashflows beginning
in late 2013, contingent upon, among other
things, receipt of permits in a timely manner.
The high-iron laterite and limestone deposits
occur 1km from the coast, which is expected
to minimize transportation costs due to
the proximity of the mine pit to the port. The
upper portions of the laterite profile comprise
the ferruginous zone and limonite
zone, both rich in iron. The deposit is expected
to be developed as a surface mining
operation with the high-iron material sold to
the Chinese iron ore market.
Beneath this zone is the higher nickel
grade saprolite zone, which will be the dominant
feed for a new processing facility
under consideration by the Project Execution/Technology
Development team. The
high-iron DSO operation is expected to generate
early cashflow before the plant is
built and put into operation.
42 | ASIA Miner | May/June 2013