Introduction
 The Lapointe Kimberlite Pipe was discovered 80 km southeast of Timmins, Ontario. A selection of both micro- and macro-diamonds were recovered from caustic fusion analyses of just under 4 tonnes of kimberlite from delineation drilling of the Lapointe Pipe. The largest diamond, a +2.4 mm stone, is described as clear and white, and weighs 0.0665 carats and was recovered from the first 4 drill holes at the Kennecott lab in Thunder Bay, Ontario. Another set of diamond fragments recovered from the caustic fusion tests from the additional drilling were completed at SRC Laboratories in Saskatechewan and included 70 stones that were measured to be greater than 0.5 mm in one dimension. This series of results suggests that the Lapointe Kimberlite has a possible coarse diamond size distribution (refer to Table 1). SGS-Lakefield Labs in Ontario reported a single micro-diamond which remained on the +212 micron screen from 198.5 kg. The Lapointe Kimberlite was discovered on May 18, 2005 within the first hole drilled by Tres-Or. Please see CASE STUDY: LAPOINTE KIMBERLITE DISCOVERY (PDF)
Regional Geology
 The geology of northeastern Ontario and Quebec is considered favorable for primary diamond deposits due to the underlying Archean Superior craton that has been stable for at least 2.5 billion years and major, deep structures favorable for the ascending kimberlite magmas such as the Lake Timiskaming Structural Zone. This is supported by research and exploration results that demonstrate the upper mantle in eastern Canada is significantly diamond-bearing.
The Lapointe Kimberlite is a large, multiphase pipe in excess of 21 hectares in surface extent, based on airborne magnetics and the initial delineation drill program completed in 2007. The 3,500 metre delineation drill program was designed to test all parts of the body, which has been shown to be comprised of at least 6 intrusive events, each of which has returned diamonds. The initial encouraging diamond recovery which included 440 diamonds in less than 4 tonnes of kimberlite processed by caustic fusion, backed up by favourable indicator mineral chemistry (including sub-calcic [G10] pyropes and eclogite garnets with compositions similar to inclusions in diamonds) has led to the recommendation to complete a 50 tonne extraction test to verify the possible coarse size distribution based in the initial results.
Airborne Magnetics-Horizontal gradient shows the Lapointe 1 target referred to in our May 12, 2005 news release. The background is the horizontal gradient of the total magnetic field data. The Lapointe 1 priority target in the in the centre top of image is a large coincident magnetic, electromagnetic, and indicator mineral target that appears to be comprised of two coalescing lobes. The horizontal gradient is used on the magnetic data as it highlights the edges of the rock creating the magnetic anomaly. Kimberlites which have a vertical pipe like shape show up as donut shaped anomalies. The diabase dykes in the area (not of economic interest) show up like railway tracks. The red outlines show the land position. The multi-coloured pies depict the kimberlite indicator mineral results taken down ice of the Lapointe 1 target. The size of the pie is related to the number of indicator minerals in the sample. The colours represent the different types of indicator minerals. Red for pyrope garnets, Blue for ilmenite, Green for chrome diopside, Orange for eclogitic garnet and Brown for chromite. (refer to Airborne Magnetics-Horizontal gradient) and (Till Chemistry)
Exploration
 Tres-Or discovered the largest diamond-bearing kimberlite in Ontario, the Lapointe Kimberlite Pipe, located about 80 km southeast of Timmins, Ontario in May 2005. In March 2007, two 21-year surface and mineral rights leases were granted to Tres-Or by the Province of Ontario. The total area of the leases is 388.7 hectares and covers the +21 hectare Lapointe pipe and surrounding lands.
Caustic fusion tests from less than 4 tonnes of kimberlite have yielded 440 diamonds from the initial delineation drilling program. During the year, Tres-Or successfully recovered a large sample of the Lapointe Kimberlite. Collection of the sample employed a large diameter RC rig contracted from North West Sequoia Drilling Ltd. The vertical, large diameter RC rig used 20 inch casing set into competent overburden in the central part of the Lapointe Pipe. The top of the kimberlite was reached at approximately 81 m depth and the kimberlite extraction and collection continued to a vertical depth of 260.5 m. This single hole collected more than 50 tonnes of kimberlite.
The large tonnage sample was shipped to a secure storage facility pending the engagement of a DMS plant facility to process the kimberlite for macro-diamond content.
Caustic fusion tests of almost 4 tonnes of the Lapointe Kimberlite have returned results suggestive of a potentially low-grade but coarse size distribution. Such hints of a coarse size distribution warrant further examination due to the large size of the body (+21 hectares) and low mining costs in the area. The primary goal of the 50 tonne test is to recover macro-diamonds and confirm the coarse size distribution.
The Lapointe pipe is a large (+21 hectares in size), multiphase intrusive. Diamonds were recovered from all phases of the Lapointe kimberlite during the initial drilling. The Lapointe pipe has yielded 440 diamonds from 3687 kilograms (kg) of undiluted kimberlite from caustic fusion tests (4236 kg starting weight). The largest diamond is a clear white gemstone weighing 0.0665 carats that remains on +1.7 mm screen. Six other diamonds weigh between 0.0024 and 0.0100 carats. In total 5 stones are greater than or equal to 1.0 mm in at least one measured dimension, 50 diamonds are greater than or equal to 0.5 mm in at least 1 dimension, and 14 diamonds are greater than or equal to 0.5 mm in 2 measured dimensions. The total weight of diamond recovered is 0.147 carats. The total caustic results are tabulated by sieve size and are reported below (Table 1):
Table 1: Cumulative caustic fusion results for the Lapointe Kimberlite presented by sieve size.
The results tabulated above in Table 1 include selective replicate testing of the highest diamond count phase from the deep central part of the pipe. This replicate sampling used the 2nd half split of core, and recovered 0.025 carats of diamonds from 36.5 kg of kimberlite (see news release dated March 6, 2006).
Before testing, the core was ½ split and logged, with one half split being bagged into 8 kg batches, and the 2nd half split being retained for further geological examination, and replicate sampling where warranted. Large crustal xenoliths were excluded from processing. The fully diluted weight for the tested drill interval is 4236 kg, with much of the dilution occurring near the northern pipe contact.
The caustic tests were conducted at 3 independent Canadian laboratories (Saskatchewan Research Council (SRC), SGS-Lakefield Research Limited, and Thunder Bay Diamond Laboratory), using bottom screen sizes of 0.150 mm or 0.106 mm. Majority of the samples were processed at SRC, using the 0.106 mm bottom screen size. Each of the labs returned at least some micro-diamonds.
More than 95% of the recovered diamonds, both by count and weight, are sourced from the central-western portion of pipe, which accounts for less than half the total weight of kimberlite tested. This area of potential diamond concentration is estimated to be between 4 to 10 hectares, and is the area where the large, 50 tonne test sample was successfully extracted in February 2008.
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