XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3791
Côté Gold is located on Treaty 9 territory, on the tradi-
tional lands of Mattagami First Nation and Flying Post
First Nation as well as within the traditional harvesting area
of the Abitibi Inland Historic Métis Community, Métis
Nation of Ontario Region 3.
The project is currently operated as a joint venture
between IAMGOLD Corporation (“IAMGOLD”), as
the operator, and Sumitomo Metal Mining Co., Ltd.
(“Sumitomo”). This open pit mine and processing plant
is of significance and will be one of Canada’s largest gold
operations.
During the project’s prefeasibility study a comprehen-
sive circuit review was conducted based on the 2009–2015
drilled and sampled material. The Côté mineralization is
free-milling (non-refractory) of which a portion of the
gold liberates during grinding and is amenable to gravity
concentration and the response to gravity and leaching
is relatively consistent across head grades. Therefore, the
lower-grade gold material is expected to exhibit the same
level of metal extraction.
The Côté gold deposit is a new Archean low-grade,
high-tonnage gold (± copper) discovery. It is described as a
synvolcanic intrusion related and stockwork-disseminated
gold deposit and appears to correspond to the porphyry
style. Due to the ore being classified as very competent and
abrasive, the comminution circuit review included a com-
parison between traditional deployment of SABC circuit
versus a HPGR-ball mill circuit prior to gravity concentra-
tion and cyanide leaching.
At the time of the prefeasibility, the estimated ore
reserve considered 196 Mt of ore to be mined in an open-
pit design, scheduling for a 60Mt/year mining with 32 kt/
day processing capacity and corresponding 16 years life of
mine (LOM). As the studies and project developed, the
mining rate was increased to 69Mt/year and 18 years of
mine life.
CIRCUIT CONSIDERATIONS
In order to effectively liberate the gold from the gangue a
series of size reduction and classification steps are required
before the mineral particles can be separated in the com-
bined gravity and leaching recovery circuit. Given the sub-
stantial scale of the project, the run-of-mine ore requires
to be crushed by a gyratory primary crusher followed by
either a SABC circuit or secondary crusher – HPGR – ball
mill circuit.
Apart from the volume of ore to be processed, the
rock’s breakage characteristics have a profound impact on
the energy requirement of the processing plant. This is not
only limited to the energy consumed for size reduction but
sahould be reviewed more broadly in areas of material han-
dling (e.g., in relation to recirculating loads), and grind-
ing media consumption (high embodied energy) as well.
Subsequentially, the selection of the processing equipment
and associated relation between energy input translating
to actual size reduction will influence operating costs. The
circuit requires to be robust and flexible to handle poten-
tial geological feed variations during the life of mine of the
deposit. Comminution and ore variability test work was
reported as per Table 1.
The comminution tests indicated that the ore was very
competent, particularly demonstrated by most composites
being measured with A × B below 30. Also, the abrasion
index has a dominant influence on operating costs, apart
from the value reported in Table 1, additional compos-
ite test work measured an increased value of 0.68 g and
comparison between both the main Côté deposit and the
Gosselin deposit under exploration demonstrated to be
similar (Figure 2).
The feed consistency (or variability) to the recovery cir-
cuit will determine the efficiency as stability will improve
recovery rates (Runge et el.,2024). Amelunxen et al. have
reported that compared to SABC circuits, HPGRs show
improved stability in output which supports the notion of
Table 1. Comminution characteristics Côté Lake deposit
(refer to NI 43-101 TECHNICAL REPORT)
Metric Unit Value
Bond ball work index kWh/t 15.89
Bond abrasion index g 0.55
A × b [-]25.98
A × b (2017 composite) [-]24 (maximum value)
Figure 1. Project location
Côté Gold is located on Treaty 9 territory, on the tradi-
tional lands of Mattagami First Nation and Flying Post
First Nation as well as within the traditional harvesting area
of the Abitibi Inland Historic Métis Community, Métis
Nation of Ontario Region 3.
The project is currently operated as a joint venture
between IAMGOLD Corporation (“IAMGOLD”), as
the operator, and Sumitomo Metal Mining Co., Ltd.
(“Sumitomo”). This open pit mine and processing plant
is of significance and will be one of Canada’s largest gold
operations.
During the project’s prefeasibility study a comprehen-
sive circuit review was conducted based on the 2009–2015
drilled and sampled material. The Côté mineralization is
free-milling (non-refractory) of which a portion of the
gold liberates during grinding and is amenable to gravity
concentration and the response to gravity and leaching
is relatively consistent across head grades. Therefore, the
lower-grade gold material is expected to exhibit the same
level of metal extraction.
The Côté gold deposit is a new Archean low-grade,
high-tonnage gold (± copper) discovery. It is described as a
synvolcanic intrusion related and stockwork-disseminated
gold deposit and appears to correspond to the porphyry
style. Due to the ore being classified as very competent and
abrasive, the comminution circuit review included a com-
parison between traditional deployment of SABC circuit
versus a HPGR-ball mill circuit prior to gravity concentra-
tion and cyanide leaching.
At the time of the prefeasibility, the estimated ore
reserve considered 196 Mt of ore to be mined in an open-
pit design, scheduling for a 60Mt/year mining with 32 kt/
day processing capacity and corresponding 16 years life of
mine (LOM). As the studies and project developed, the
mining rate was increased to 69Mt/year and 18 years of
mine life.
CIRCUIT CONSIDERATIONS
In order to effectively liberate the gold from the gangue a
series of size reduction and classification steps are required
before the mineral particles can be separated in the com-
bined gravity and leaching recovery circuit. Given the sub-
stantial scale of the project, the run-of-mine ore requires
to be crushed by a gyratory primary crusher followed by
either a SABC circuit or secondary crusher – HPGR – ball
mill circuit.
Apart from the volume of ore to be processed, the
rock’s breakage characteristics have a profound impact on
the energy requirement of the processing plant. This is not
only limited to the energy consumed for size reduction but
sahould be reviewed more broadly in areas of material han-
dling (e.g., in relation to recirculating loads), and grind-
ing media consumption (high embodied energy) as well.
Subsequentially, the selection of the processing equipment
and associated relation between energy input translating
to actual size reduction will influence operating costs. The
circuit requires to be robust and flexible to handle poten-
tial geological feed variations during the life of mine of the
deposit. Comminution and ore variability test work was
reported as per Table 1.
The comminution tests indicated that the ore was very
competent, particularly demonstrated by most composites
being measured with A × B below 30. Also, the abrasion
index has a dominant influence on operating costs, apart
from the value reported in Table 1, additional compos-
ite test work measured an increased value of 0.68 g and
comparison between both the main Côté deposit and the
Gosselin deposit under exploration demonstrated to be
similar (Figure 2).
The feed consistency (or variability) to the recovery cir-
cuit will determine the efficiency as stability will improve
recovery rates (Runge et el.,2024). Amelunxen et al. have
reported that compared to SABC circuits, HPGRs show
improved stability in output which supports the notion of
Table 1. Comminution characteristics Côté Lake deposit
(refer to NI 43-101 TECHNICAL REPORT)
Metric Unit Value
Bond ball work index kWh/t 15.89
Bond abrasion index g 0.55
A × b [-]25.98
A × b (2017 composite) [-]24 (maximum value)
Figure 1. Project location