An updated mineral resource estimate was completed by Mineral Services Canada Inc. taking into account mining activities at Karowe since the start of production in April 2012 and includes changes to the geological model, re-interpretation of diamond size distributions, and the results of all diamond sales.
The updated mineral resource was completed to the standards of the Canadian Institute of Mining (CIM) Definition Standards for Mineral Resources and Reserves as incorporated by National Instrument 43-101 Standards of Disclosure for Mineral Projects. The update incorporates a comprehensive review of the historic exploration data and resource modeling information (News Release dated 29/03/2010), complemented with data generated since the start of production in April 2012.
Updated Mineral Resource Estimate as at October 21, 2013* (recoverable based on current plant operating parameters, 1.25mm bottom cut-off).
(400m to 750m)
*Since the start of production in April 2012, 5.50 million tonnes of kimberlite have been mined, with 3.46 million tonnes processed through the plant resulting in the recovery of 690,000 carats of diamonds. The remainder of material mined has been stockpiled for processing during mining and towards the end of the life of the current open-pit. Stockpile material is not included in Table 1.
The reader is cautioned that mineral resources that are not mineral reserves do not have demonstrated economic viability. Estimates of recoverable carats are based on the current Karowe plant configuration and physical ore characteristics (in particular ore hardness), and may be influenced by any changes to these factors.
Updated diamond value estimates (Table 2) are based on size distribution models for each lobe (North, Centre, South) and the pricebook value of specific production batches attributable to individual lobes, referenced to a common November 2013 diamond price book. Pricing information was provided by GTD Diamonds, diamond valuation experts managing the sales of all Karowe diamonds. The price model for the +10.8 carat diamonds ('specials') is based on actual sales data.
Updated estimates of average diamond value* by lobe and resource classification
Modelled $/ carat
(400m to 750m)
*US dollars per carat: recoverable based on current plant operating parameters, 1.25mm bottom cut-off size.
The full details of the mineral resource update will form a portion of a NI 43-101 Technical report to be filed on www.sedar.com within 45 days.