Two separate graphite bearing bands have been mapped each having an estimated width greater than 50 meters. These bands were traced for a strike distance of 1.6 km. At their southern extent these graphite bearing bands appear to coalesce to form a single irregularly shape lenticular pod having a width in excess of 250 meters.
At the northern margins, the graphite bearing unit is exposed in the stream as flat outcrop several meters across where character of graphite mineralization can be more clearly observed. Graphite lenticles having thickness of up to 4 mm and lengths of several cm occur as intra-folia concentrations between the mica rich layers of the schist. These lenses and lenticles are composed of mostly massive flake graphite. The thickest graphite rich band observed was approx. 3cm in thickness as a fracture filling associated with crenulated mica rich schist. Most graphite rich lenticles, however, are mm in thickness and or they occur as graphite smears on sheared surfaces.
Samples 97280 and 97315 are composite bulk samples that combined freshly broken grab samples taken from different outcrops localities 10's of metre apart at the sample locality. Each bulk sample size was approximately 15 kg in weight. Composite sample 97280 was taken at the northern part of the flat lying graphite bearing unit outcropping in the stream bed. Composite sample 97315 was taken from a steeply sloping outcrop at the southern portion of the graphite showing where it has the widest width. No attempt was made to select the samples as to truly represent of the average grade of graphite at each locality.
The samples were submitted to Activation Laboratories Ltd.(Actlabs), Ancaster, Ontario for Mineral Liberation Analysis (MLA). The sample was crushed to -2mm particle size (- 10 mesh) and split using the A Jones riffle splitter until a 500 g sample was obtained. The 500 g sample was screened to +106/-850 micron (+150 mesh/-20mesh) screen openings. Five grams of the crushed sample in the size range greater than 160 microns and less than 850 microns was taken from each sample and prepared as two polished sections. MLA scanning electron microscope analyses determined the purity of individual graphite flakes within individual size categories and percentage content of associated host minerals.
The report from Actlab concluded that "approximately 80% of the graphite flakes in sample 97280 and 90% in 97315 contain inclusions or are incorporated within phyllosilicates, quartz and feldspars." The respective samples for the total fraction range indicated, "shows presence of 2.19 and 4.67% pure graphite, respectively. Fine mixture of graphite and mineral matter accounts for approximately 5.81 wt% of sample 97280 and 13.52 wt% of sample 97315" ( Actlab Laboratory Report No.A12-12401 December 10, 2012). The total graphite content in the large bulk sample was not separated from the host mineral component during an MLA analysis but was estimated by petrographic modal counts on sieved fractions of crushed material prepared as a polished thin section.
Naturally the range of flake sizes is considerably smaller than the diameter of the crushed fragments captured on the individual screens. This study confirms that the form of graphite is flake graphite that range from 250 microns to 6 microns in size. Less than 15% of the free graphite have sizes greater than100 microns. As noted earlier, given the nature of sampling these observed statistics may be biased to the low side.
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