The Mont-Wright and Fire Lake mines are part of the highly-folded and metamorphosed southwestern branch of the Labrador Trough. The most important rock type in the area is the specular hematite iron formation forming wide, massive deposits that often form the crest of high ridges extending for many kilometers in the Quebec Labrador area.

The Labrador Trough consists of Paleoproterozoic sedimentary and volcanic rocks that extends for more than 1100 km, from the northwest corner of Ungava Bay south to Lake Pletpi. It forms the western part of a larger orogenic belt called the New Québec Orogen¸ which records the oblique convergence and collision of the Archean Superior Craton to the west and an Archean core zone to the east. The Labrador Trough largely represents a foreland basin and comprises three sedimentary cycles, which are together referred to as the Kaniapiskau Supergroup.

The Mont-Wright mining complex and Fire Lake mine run day and night, 365 days a year, to produce more than 26 million metric tons of iron ore concentrate every year.

The Mont-Wright mining complex
This sector of AMEM consists of an open-pit mine, huge pieces of mining equipment, the crusher, concentrator, gigantic maintenance workshops, a warehouse with massive rooms and a train loading system.

The mine is 24 square kilometers in area. Its mineral resources amount to 5.6 billion metric tons of ore and the current mining plan runs up to 2045. Other plans are being studied to increase the production of concentrate and continue mining.

Generally speaking, 2.6 metric tons or raw ore need to be extracted from the ground to produce one metric ton of iron ore concentrate. Drill operators drill deep 16-meter holes in line with a predetermined plan. These holes are filled with an explosive mixture that smashes the rock by blasting.

Once the rock is fragmented by blasting, it is loaded onto giant trucks by powerful shovels. The buckets of some of them have a capacity of 60 cubic verges (yards) and three or four loads are all it takes to load our largest 400-metric ton trucks – the first to make their appearance in Québec.

The Fire Lake mine
55 kilometers south of the Mont-Wright mining complex is the Fire Lake open-pit mine, in operation since 2006. Initially mined on a semi-annual basis, since 2012 the site has been mined all year round. The iron content of the ore mined is higher than for the Mont-Wright mine. The contribution of this ore has an important role to play in increasing the company’s production in the coming years.

Fire Lake is an extraction mining site without a crusher or concentrator. Mining activities are carried out as at Mont-Wright but the mining equipment is smaller in size.

All the raw ore from Fire Lake travels to Mont-Wright by train four times a day on average. Convoys of sixty or so wagons use the railroad segment linking Fire Lake to the main railroad. The ton of raw ore from this mine are unloaded, crushed and concentrated at the Mont-Wright mining complex. The concentrate obtained is also carried by train to Port-Cartier.

Given the quality of the ore extracted from Fire Lake, the tonnage extracted is likely to increase.

The ore is crushed in two gyratory crushers and the concentrator operates with seven lines of three stage spiral classifiers and horizontal filters.

The concentrator at Mont-Wright consists of 8 silos to continuously receive the raw material crushed in the crusher. The blocks contained in the silos are carried to one of the seven autogenous grinders: the blocks of ore are broken down as they knock together. On leaving the grinders, the particles are sieved by vibration. The particles that are too large are returned to the grinding process and the others are directed to circuits of spirals for the concentration stage.

The 8,500 spirals enable the iron content of the raw ore to be increased via a centrifugal force principle: by adding water, the iron particles that are heavier than the tailings are separated by gravity. Concentrate with an iron content of over 66% is obtained while the tailings (mainly silica, better known as sand) is carried to the containment area that will be restored when mining is finished.

Once the water has been removed from the Mont-Wright concentrate, it is taken to the silo for loading onto trains that carry it to Port-Cartier, in four or five convoys a day.

Fire Lake is an extraction mining site without a crusher or concentrator.

The pelleting process operates with two production lines and its main stages can be summarised as follows:
- enrichment of the concentrate
- crushing of the concentrate
- filtration
- integration of additives and mixing
- sintering
- sieving
- baking.

The plant at Port-Cartier has enrichment facilities that enable the silica in the concentrate to be reduced if necessary, according to customer requirements for higher quality pellets.

After this optional stage, the concentrate is taken to one of the six grinding balls with water and additives. As they knock together inside the grinders, the balls – made of a very hard alloy – reduce the particles of concentrate to the size of a grain of dust.

The material obtained which resembles mud is pumped to one of the 10 vertical filters for partial drying. After this stage, the substance called filter cake is tipped into one of the three mixers where other additives are incorporated.

This mixture is taken into one of the 10 sintering disks positioned diagonally. These large saucers turn on themselves, forming the pellets with a rotating movement thanks to the centrifugal force and angle of the equipment.

The pellets then move to the sieving section which enables those of the right size to be selected. Pellets that are too large or small are redirected to the disks, while the ones of the right size are sent to the last stage, hardening. To do this, the brittle pellets (also called “green” pellets) are baked in one of the two large furnaces at a temperature of 1300 degrees Celsius.