The classification scheme most widely accepted for graphite deposits was introduced by Cameron (1960). It classifies known graphite deposits into five categories reflecting the different types of graphite. The five types of deposits are:
- Disseminated flake graphite in silica-rich meta-sediments;
- Disseminated flake graphite in marbles;
- Metamorphosed coal seams;
- Vein deposits; and,
- Contact metasomatic or hydrothermal deposits in metamorphosed calcareous sediments or marble.

The Bissett Creek Project would fall within the first category.

At Bissett Creek, the graphite mineralization is well characterized by homogeneously distributed graphite flakes (about 1 to 5 mm in size and 3 to 10% of volume) within biotite schists with variable content of amphibole, clinopyroxene, chlorite, carbonate and graphite. Ubiquitous trace minerals included sphene, apatite, garnet and zircon. Sulfides were reported as trace amounts, usually as pyrite and pyrrhotite. On the basis of the graphite content and variation of the gneissic facies, the graphitic gneiss can be divided into:
- Biotite rich quartzo-feldspathic and graphitic gneiss, paragneiss;
- Biotite rich quartzo-feldspathic and graphitic gneiss; and,
- Diopside-tremolite-biotite rich quartzo-feldspathic and graphitic gneiss.

Graphite flakes occur disseminated in the graphitic gneiss horizon and are in variable concentration in the transitional gneiss. The diopside-tremolite-biotite-graphite bearing gneiss is mostly located in the upper part of the mineralized graphitic horizon whereas the graphite rich paragneiss (up to 10% graphite) subunit generally confined at the base. Graphite generally forms slender, oval to sub-rounded planar flakes averaging 0.3-1.5 mm long and 0.03-0.07 mm wide. These commonly occur adjacent to flakes of biotite of similar size or are associated with patches of pyrrhotite. Much less commonly, books of a few flakes are contorted or warped, and minor quartz or less commonly biotite occurs between the individual flakes.

The overall size distribution of the graphite flakes observed in core samples throughout the deposit does not show a direct relationship to the total graphitic carbon of the analysis. Large flakes are generally present independently of the percentage grade of the graphite, making the graphite gneiss horizon prospective along its entire length.

It was noted that the weathered horizon, some 2-4 m thick, was a more friable form of the gneiss that the fresher rock without any noticeable change in the graphite content or flake size. This weathered material has the potential to be comminuted much more easily than the fresh rock and with probably better liberation of full-sized graphite flakes.

Northern Graphite worked together with Toromont to examine the proper fleet for the given production rates. This fleet was determined to be a combination of two front-end-loaders with standard 6.4 m3 rock buckets and four haul trucks with 71 tonne capacity. A Cat 336E backhoe will support the pit operations with water control and also final cleaning along the footwall and barren gneiss contacts to minimize dilution. It would pile the material for loading by the front end loaders rather than trying to direct load the trucks.

Supporting the mining fleet will be two Cat D7E class dozers and a Cat 14M grader. Northern Graphite currently has a grader of equivalent size on site. This would be replaced in year five with a new machine. A sanding truck for winter conditions is also included. Equipment replacement has been scheduled at every five years for the frontend loaders and graders, and seven years for the haul trucks and dozers. The support backhoe is replaced every ten years.

Mining will be done on three metre benches in the mill feed to minimize the dilution. Where possible the benches will be mined at six metres in waste and continuous mill feed sections. Final cleaning of the footwall will be completed under grade control supervision with the frontend loader when the slope will allow it or with the backhoe pulling the material into a windrow for the front end loader to load.

For the operating cost determination, mine haul profiles were developed for each bench and phase to the various stockpile locations. They also included haul profiles for placement of material backfilling the pit. The benefit of backfilling the pit is reduced disturbance to the environment, reduced operating costs and reduced final reclamation as it will be completed concurrent with mining.

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Graphite Flotation
Flash flotation cell concentrate is reground in a 7 ft x 10 ft, 150 kW pebble mill (622-ML-002) operating in open circuit. The pebble mill is operating with a light load such as to minimize degradation of the coarse graphite flakes. It is preferred to use small low density, non-metallic, spherical or short axis cylindrical grinding media, suitably 12.5 mm in diameter available commercially as Cylpebs. Such milling of the graphite concentrate serves to effectively polish the flakes surfaces so that resulting discharge from the mill may be easily concentrated, via flotation cleaners, to a level of 95% Cg.

The discharge of the regrind mill is being pumped (622-PP-003, 004) to the 1.22 m diameter x 6 m high flotation column primary cleaner (631-FC-003). Flash cell tailings are pumped (622-PP-001, 002) to a set of 4 x 15 in cyclones (with one cyclone stand-by) (622-CY001). The cyclones underflow flows by gravity to a 10 ft x 16 ft, 700 kW regrind ball mil ........