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Post by Franko10 ™ on Jan 31, 2005 15:24:37 GMT -5
Kensington Resources Ltd.: Microdiamond Results for FALC 150 Core
VICTORIA, British Columbia -- Kensington Resources Ltd. (TSX VENTURE:KRT) (the "Company") announces that it has received from the operator, De Beers Canada Exploration Inc., microdiamond results from the Kimberley Microdiamond Lab (KMDL) for Kimberlite Body 150 of the Fort a la Corne Diamond Project in east-central Saskatchewan.
Kimberlite 150 was selected for delineation drilling and microdiamond sampling in Fall 2003 due to favourable historical diamond recoveries and its size. The new results were combined with historical data from the 150 body in order to make grade forecasts based on stone size distributions. Both the new data and the grade forecasts by Mineral Resource Management (MRM) of De Beers do not support further drilling and sampling work on this kimberlite but efforts on the other prospective bodies will continue under the current, accelerated program. The 2004 - 2005 evaluation and exploration program, budgeted at $7.62 million, represents the largest and most aggressive program to date at Fort a la Corne.
"While the diamond recoveries from Kimberlite 150 were lower than expected, the Joint Venture partners remain committed in their current strategy of focusing on enriched zones in a number of other proximally-located priority kimberlites bodies including 140/141, 148 and 122," stated Robert McCallum, President and CEO of Kensington. "Past results from these bodies have been very encouraging and in the upcoming meetings of the Joint Venture Management Committee, we will be examining ways to accelerate a development decision on the Fort a la Corne Project."
Representative slabbed core samples were collected from 12 HQ coreholes widely spaced across the 150 body. A total of 392 microdiamonds were recovered from 51 samples utilizing caustic dissolution methods on 422 kilograms of core submitted to the Saskatchewan Research Council (SRC). The SRC recovered and reported diamonds down to a lower cutoff of 0.075 millimetres in size; diamonds passing through a 0.075 mm screen were not included in the stone tallies. The SRC reported 98.6% recovery of internal tracers during diamond recovery and stone picking was routinely audited by a supervisor.
Recovered diamonds and selected caustic residues were sent to the De Beers' Kimberley Microdiamond Laboratory (KMDL) for further auditing and verification of individual stone size, shape, and sieve category using proprietary techniques. KMDL reported 238 stones with dimensions equivalent to a +74 micron sieve cut-off and having a combined weight of 0.248 carats including one macrodiamond weighing 0.226 carats recovered in the 2 mm sieve category. The average diamond grade for all samples was 5.7 stones per 10 kg utilizing only stones greater than 74 microns.
Due to geological complexity in the 150 kimberlite body, the results from the 2003 drillholes were divided into three groups corresponding to the three areal lobes of the kimberlite outline (Table One). Diamond results by kimberlite type and sieve category are shown in Table Two.
Table One: 150 Microdiamond Results by Kimberlite Type
---------------------------------------------------------------------
Micro-
diamond
Abundance
greater
Total Stones than 74 Stones
150 Sample Carat greater microns larger
Kimberlite Mass Total Weight than 74 (stones/ than
Area (kg) Stones (octacarats) microns 10 kg) 0.5 mm
---------------------------------------------------------------------
North Lobe 82.7 80 394,500 47 5.7
---------------------------------------------------------------------
West Lobe 239.5 258 24,332,850 161 6.7 1;
0.226 cts.
---------------------------------------------------------------------
South Lobe 99.5 54 183,400 31 3.1
---------------------------------------------------------------------
Total 421.7 392 24,910,750 239 Average
of 5.7
---------------------------------------------------------------------
One octacarat is equivalent to 1x10(-8) carats
Table Two: KMDL 150 Microdiamond Results (greater than 74 microns)
by Sieve Category and Kimberlite Type
---------------------------------------------------------------------
Kimberlite +0.074mm +0.106mm +0.150mm +0.212mm
Type Sieve Sieve Sieve Sieve
---------------------------------------------------------------------
North Lobe 22 18 3 4
---------------------------------------------------------------------
West Lobe 78 49 25 6
---------------------------------------------------------------------
South Lobe 18 9 3 1
---------------------------------------------------------------------
Total 118 76 31 11
---------------------------------------------------------------------
---------------------------------------------------------------------
+0.600 to
Kimberlite +0.300mm +0.425mm +0.850 mm +2 mm
Type Sieve Sieve Sieves Sieve
---------------------------------------------------------------------
North Lobe 0 0 0 0
---------------------------------------------------------------------
West Lobe 2 0 0 1
---------------------------------------------------------------------
South Lobe 0 0 0 0
---------------------------------------------------------------------
Total 2 0 0 1
---------------------------------------------------------------------
In terms of stone size fractions, approximately 49.4% of the stones were recovered on the 0.074 mm sieve and 94.1% of the stones were retained in sieves less than 0.212 mm (Table 2). However, 91% of the total carat weight of diamond from these samples was recovered in a single stone from the west lobe. Viewed in isolation, microdiamond stone counts can be misleading and the estimation of macrodiamond grade from microdiamond results will require an interpretation of the diamond grade-size plots.
The 2003 microdiamond dataset was made available for modeling grade estimates by MRM. From the combined dataset of historical and new results, 352 microdiamonds from the west lobe were available for modeling, of which 46 were re-categorized as less than 74 microns in size, and therefore not used. Due to the prevalence of stones in only four size classes, historical macrodiamond data for 56 stones was utilized to stabilize the grade-size curve. The grade forecast for this lobe is 3 cpht and encompasses an estimated mass of 68 million tonnes of kimberlite based on integration of drillhole information and geophysical data. Currently, confidence limits for the modeled data are not available.
Modeling of the south lobe of the body utilized 129 microdiamonds (23 unused stones were categorized as less than 74 microns in size) grouped into four size categories. Only 15 macrodiamonds were recovered from this lobe in the past and this number of stones was insufficient to include in the modeling. The south lobe was assigned a forecast grade of 3 cpht encompassing a mass of 50.5 million tonnes based on integration of drillhole information and geophysical data. The north lobe was not modeled due to the availability of only 67 microdiamonds and no historical macrodiamonds. The estimated mass for this lobe is 32.1 tonnes.
VICTORIA, British Columbia -- Kensington Resources Ltd. (TSX VENTURE:KRT) (the "Company") announces that it has received from the operator, De Beers Canada Exploration Inc., microdiamond results from the Kimberley Microdiamond Lab (KMDL) for Kimberlite Body 150 of the Fort a la Corne Diamond Project in east-central Saskatchewan.
Kimberlite 150 was selected for delineation drilling and microdiamond sampling in Fall 2003 due to favourable historical diamond recoveries and its size. The new results were combined with historical data from the 150 body in order to make grade forecasts based on stone size distributions. Both the new data and the grade forecasts by Mineral Resource Management (MRM) of De Beers do not support further drilling and sampling work on this kimberlite but efforts on the other prospective bodies will continue under the current, accelerated program. The 2004 - 2005 evaluation and exploration program, budgeted at $7.62 million, represents the largest and most aggressive program to date at Fort a la Corne.
"While the diamond recoveries from Kimberlite 150 were lower than expected, the Joint Venture partners remain committed in their current strategy of focusing on enriched zones in a number of other proximally-located priority kimberlites bodies including 140/141, 148 and 122," stated Robert McCallum, President and CEO of Kensington. "Past results from these bodies have been very encouraging and in the upcoming meetings of the Joint Venture Management Committee, we will be examining ways to accelerate a development decision on the Fort a la Corne Project."
Representative slabbed core samples were collected from 12 HQ coreholes widely spaced across the 150 body. A total of 392 microdiamonds were recovered from 51 samples utilizing caustic dissolution methods on 422 kilograms of core submitted to the Saskatchewan Research Council (SRC). The SRC recovered and reported diamonds down to a lower cutoff of 0.075 millimetres in size; diamonds passing through a 0.075 mm screen were not included in the stone tallies. The SRC reported 98.6% recovery of internal tracers during diamond recovery and stone picking was routinely audited by a supervisor.
Recovered diamonds and selected caustic residues were sent to the De Beers' Kimberley Microdiamond Laboratory (KMDL) for further auditing and verification of individual stone size, shape, and sieve category using proprietary techniques. KMDL reported 238 stones with dimensions equivalent to a +74 micron sieve cut-off and having a combined weight of 0.248 carats including one macrodiamond weighing 0.226 carats recovered in the 2 mm sieve category. The average diamond grade for all samples was 5.7 stones per 10 kg utilizing only stones greater than 74 microns.
Due to geological complexity in the 150 kimberlite body, the results from the 2003 drillholes were divided into three groups corresponding to the three areal lobes of the kimberlite outline (Table One). Diamond results by kimberlite type and sieve category are shown in Table Two.
Table One: 150 Microdiamond Results by Kimberlite Type
---------------------------------------------------------------------
Micro-
diamond
Abundance
greater
Total Stones than 74 Stones
150 Sample Carat greater microns larger
Kimberlite Mass Total Weight than 74 (stones/ than
Area (kg) Stones (octacarats) microns 10 kg) 0.5 mm
---------------------------------------------------------------------
North Lobe 82.7 80 394,500 47 5.7
---------------------------------------------------------------------
West Lobe 239.5 258 24,332,850 161 6.7 1;
0.226 cts.
---------------------------------------------------------------------
South Lobe 99.5 54 183,400 31 3.1
---------------------------------------------------------------------
Total 421.7 392 24,910,750 239 Average
of 5.7
---------------------------------------------------------------------
One octacarat is equivalent to 1x10(-8) carats
Table Two: KMDL 150 Microdiamond Results (greater than 74 microns)
by Sieve Category and Kimberlite Type
---------------------------------------------------------------------
Kimberlite +0.074mm +0.106mm +0.150mm +0.212mm
Type Sieve Sieve Sieve Sieve
---------------------------------------------------------------------
North Lobe 22 18 3 4
---------------------------------------------------------------------
West Lobe 78 49 25 6
---------------------------------------------------------------------
South Lobe 18 9 3 1
---------------------------------------------------------------------
Total 118 76 31 11
---------------------------------------------------------------------
---------------------------------------------------------------------
+0.600 to
Kimberlite +0.300mm +0.425mm +0.850 mm +2 mm
Type Sieve Sieve Sieves Sieve
---------------------------------------------------------------------
North Lobe 0 0 0 0
---------------------------------------------------------------------
West Lobe 2 0 0 1
---------------------------------------------------------------------
South Lobe 0 0 0 0
---------------------------------------------------------------------
Total 2 0 0 1
---------------------------------------------------------------------
In terms of stone size fractions, approximately 49.4% of the stones were recovered on the 0.074 mm sieve and 94.1% of the stones were retained in sieves less than 0.212 mm (Table 2). However, 91% of the total carat weight of diamond from these samples was recovered in a single stone from the west lobe. Viewed in isolation, microdiamond stone counts can be misleading and the estimation of macrodiamond grade from microdiamond results will require an interpretation of the diamond grade-size plots.
The 2003 microdiamond dataset was made available for modeling grade estimates by MRM. From the combined dataset of historical and new results, 352 microdiamonds from the west lobe were available for modeling, of which 46 were re-categorized as less than 74 microns in size, and therefore not used. Due to the prevalence of stones in only four size classes, historical macrodiamond data for 56 stones was utilized to stabilize the grade-size curve. The grade forecast for this lobe is 3 cpht and encompasses an estimated mass of 68 million tonnes of kimberlite based on integration of drillhole information and geophysical data. Currently, confidence limits for the modeled data are not available.
Modeling of the south lobe of the body utilized 129 microdiamonds (23 unused stones were categorized as less than 74 microns in size) grouped into four size categories. Only 15 macrodiamonds were recovered from this lobe in the past and this number of stones was insufficient to include in the modeling. The south lobe was assigned a forecast grade of 3 cpht encompassing a mass of 50.5 million tonnes based on integration of drillhole information and geophysical data. The north lobe was not modeled due to the availability of only 67 microdiamonds and no historical macrodiamonds. The estimated mass for this lobe is 32.1 tonnes.
