Summary:
The Project represents an example of a granulite-hosted, high temperature graphite deposit, which could be paralleled to the Sierra de Aracena metamorphic belt described by Rodas et al. (2000), where the same type of graphite occurrences are found: I) stratiform graphite associated with gneiss and quartzite interbedded with calc-silicate series; II) disseminated graphite; III) graphite associated with anatectic tonalities and their restitic enclaves and IV) graphite veins. Graphite in all types of occurrences shows high crystallinity as revealed by the x-ray diffraction (XRD) study and thermal properties (Rodas et al. 2000).
The Project area lies in the Grenville Geological Province, which is recognized as a deeply exhumed Mesoproterozoic Himalayan-type collision orogenic belt that extends over thousands of kilometres and is interpreted as a collage of gneissic terranes that were subjected to high-grade metamorphism. The Project area is included in the south portion of the Morin Terrane, composed of supracrustal rocks, commonly at granulite metamorphic facies, and intruded by several bodies of granitic to anorthositic composition. The well-banded quartzo-feldspathic gneisses were divided into two groups and quartzites were documented as very massive, well-jointed, white or pinkish rocks. Crystalline limestone (marble) appeared to correspond to two large beds. Graphite is observed as dissemination and pods/veins in the marble, skarn, and paragneiss units of the Miller Property. Several pods and veins have been identified and explored by Canada Carbon. Canada Carbon has discovered multiple new graphite mineralized showings. These include nine high-grade surface graphite showings, and large, lower-grade disseminations of graphite in marble and skarn units.
Through trenching, Canada Carbon has identified many examples of graphite mineralization associated with marble and detritical rock sequences. Numerous variations of the graphite mineralization are observed within the Project area. Graphite primarily occurs in well crystallized euhedral flakes.
Wollastonite Pods
Wollastonite-graphite mineralization is a frequent association on the Property. This mineralization form often appears in small pods of tens of centimeters in diameter and can reach up to 1.6 m in thickness. Both wollastonite and graphite form well crystallized minerals and graphite assays around 15% in these pods.
Banded Graphite Formation
Banded graphite formations are thin (1 to 5 mm) bands of graphite sandwiched between thin (1 to 10 mm) layers of graphite-quartz-feldspar, stacked closely, and reaching thicknesses of many metres. The grain sizes of this mineralization type are small (less than or equal to 1 mm). The banded formations are continuous over long distances (10 m and longer) and affected by intense folding. The average graphite content of this unit is between 5 and 10%.
Graphite Pods (Marble)
Small pods (tens of centimetres long to a couple of centimetres wide) of pure graphite are often present in the white marble units. The graphite grains are coarse (5 to 50 mm) and form euhedral flakes. Many of the pods are observed along an east-west alignment direction.
Disseminated Graphite (Marble)
In all the marble units observed, graphite occurs frequently in well crystallized, euhedral, small (1 to 5 mm) disseminated crystals. The chemical reaction between carbonate and silica might have produced calc-silicates and graphite, which seems to precipitate at the boundary of the calcsilicate and marble grains. The average graphite content in the marble is approximately 0.5% graphite.
Disseminated Graphite (Skarn)
Similar to disseminated graphite in marble, disseminated graphite in skarn occurs almost everywhere, more frequently close to marble units. In skarn units farther from marble units, sulfides are more abundant. Graphite in skarn units is often found in clumps instead of flakes and is far less homogenously distributed than in the marble units.
Graphite Veins
Graphite veins seem to follow shear or fault zones, which might be evidence of structural control of metamorphic hydrothermal fluids. They are thin, centimeter-wide, sheets of aphanitic graphite that can cover many square metres. Directions of movement of faults are registered in the graphite veins as strikes and kinks. No general directions have been observed, as they are often following folded structures.