Preparation of the resource report allowed calculation of a Target for Further Exploration (“TFFE”) that provides additional potential tonnages and contained carats that are not yet included in the Resource. The TFFE is based on projection of the diamondiferous kimberlites below the shallow depths currently included in the Resource. Calculations for a conceptual target indicate there is potential for an additional 4,090,000 to 15,880,000 carats of diamonds within the Kahuna and Notch dikes, as presented in Table 1. The potential quantity and grade of any TFFE is conceptual in nature, there is insufficient exploration to define a Mineral Resource and it is uncertain if further exploration will result in the target being delineated as a Mineral Resource.
To 15,880,000 carats of diamonds within the Kahuna and Notch dikes, as presented in Table 2.
The potential quantity and grade of any TFFE is conceptual in nature, there is insufficient exploration to define a Mineral Resource and it is uncertain if further exploration will result in the target being delineated as a Mineral Resource.
Table 2: Additional potential tonnage and carats at Kahuna and Notch
||140 – 300
||140 – 600
||110 – 300
||110 – 60
*Note that bulk sampling has established that Kahuna has a recovered grade of 1.04 cpt and Notch has a recovered grade of 0.90 cpt (at a +0.85 mm lower cut-off) as previously disclosed in the Inferred Resource. As such, the “Low Range” reduces diamond grades by about 23% and the “High Range” increases diamond grades by about 5% for Kahuna and 10% for Notch. Note the tonnes and carats have been rounded to the nearest 10,000 and may not add due to rounding.
The TFFE provides reasonable guidance for additional potential tonnage and diamond grades at Kahuna and Notch to depths of 300 – 600m, but does not include:
Any potential additional tonnage or carats from any of the six other diamondiferous kimberlites that have already been drilled, sampled and mapped on the project, such as the PST, Killiq and KD series of dikes. At PST, grades of 2.18 cpt (at a +0.85 mm lower cut-off) have been reported following bulk sampling and drilling, and a network of diamondiferous dikes has been drilled in this area. The Company believes these represent high priority targets for ongoing work, due to their significant diamond grade potential, and 800 m of additional potential strike length of the Kahuna dike, and 300 m of additional potential strike length of the Notch dike as inferred by field mapping, geophysics and geological sampling. If included, these would proportionally increase the expected volume of diamond-bearing kimberlite at these targets; however drill density remains insufficient at these locations to include these areas in the TFFE at this time.
The TFFE assumes the same kimberlite densities as the Resource Estimate, which average 1.99 t/m3 for Kahuna and 2.12 t/m3 for Notch, and assumes recovery of +1 DTC sieve size macrodiamonds. The TFFE is derived from geological volumes based on projection of the Kahuna and Notch kimberlites to depths of 300 m (low range) and 600 m (high range) vertically from surface below the extent of the current geological model, and assuming a range of potential grades. The TFFE assumes a strike length of 4.7 km for Kahuna and 2.6 km for Notch; and an average width of 2.5 m and 1.5 m, respectively. Given the assumed kimberlite dike method of emplacement, and the presently defined extent of the geological models, both ranges are considered reasonable by the report authors.