Maiden Inferred Resource Estimation
In January 2015 Dunnedin released a maiden Inferred Resource estimate from the Kahuna Diamond project, located in Nunavut, Canada. The estimate was prepared by APEX Geoscience Ltd. on the Kahuna and Notch kimberlites based on data from the 2006 – 2008 bulk sampling and drill programs completed by the past operator.
- A combined Inferred Mineral Resource of 4,018,000 carats of macrodiamonds at a 0.85 mm (+1 DTC sieve size) lower diamond cut-off, with an average grade of 1.01 carats per tonne (cpt), or 101 carats per hundred tonnes (cpht) derived from 3,987,000 tonnes of kimberlite resource.
- The kimberlites in the resource are exposed at surface and remain open to extension along strike and at depth. The average drill intercept at the Kahuna kimberlite was only 80 vertical metres, however kimberlite has been intersected at vertical depths of greater than 120 m and continuity at depth is supported by the available data.
- Indicator mineral trains and geophysics suggest the Kahuna and Notch have the potential to extend along strike into areas of thin sediment cover. Kimberlite has been intercepted in drilling along these potential extensions; however drill spacing was insufficient for inclusion in the resource. These areas will be a focus of future drilling.
- Only 2 of 8 confirmed significantly diamondiferous kimberlites (Kahuna and Notch) have sufficient drilling, bulk sampling and density definition work to be included in the inferred mineral resource at this time. Other drilled, mapped and sampled diamondiferous kimberlites include the PST, Killiq, and 4 additional kimberlite dikes located between the Notch and PST kimberlites (KD-13, 14, 16 and 18).
Drilling, surface bulk sampling, and micro- and macrodiamond data indicate the Kahuna and Notch are both single phase, macrocrystic hypabyssal kimberlite dikes having similar visual and petrographic characteristics throughout. Given their relatively simple internal geology, Kahuna and Notch were modeled as separate bodies and the Mineral Resource Estimate was established by applying average grades from surface mini-bulk samples within each geological model. Sensitivity analyses of the grades at both 0.85 and 1.18 mm cut-offs are presented in Table below:
Table 1: Inferred Mineral Resource Estimate for the Kahuna and Notch Kimberlites
Note: The reader is cautioned that Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability, and might never be converted into Reserves. Figures may not sum due to rounding. Decimal figures do not indicate added level of precision. cpt = (carats-per-tonne)
The potential diamond valuation or mining characteristics of the Kahuna and Notch kimberlites have not yet been determined. However, a 2008 evaluation of Kahuna diamond characteristics by Mineral Services Canada (MSC) describes the Kahuna diamond population as having encouraging value characteristics, with a high abundance of colourless and near colourless varieties with octahedral shapes being the dominant morphology. The Notch kimberlite displays similar diamond characteristics to Kahuna and other significantly diamondiferous kimberlites within the Kahuna Project including the PST and Killiq kimberlites.
The Company cautions that the inferred resource cannot be used to construct an economic model of the project prior to assembling a package of diamonds for valuation.
Chris Taylor, M.Sc., P.Geo, CEO of the Company is a “Qualified Person” as defined under NI 43-101 has reviewed and approved the technical content of this web page.