Chesapeake; grote resources ( 14 mio plus)
Enorme hoeveelheid boringen, open pit, en een MC van 170 mio.
Dit wordt niet mijn inzending voor de competitie, daarvoor ga ik meer risico nemen, maar een overweging voor mijn porto is het zeker.
S&J.
The Metates resource estimate is based upon a total of approximately 21,100 assays estimated from 171 drill holes totalling 63,127 meters. The resource estimate prepared by IMC used inverse distance weighting methods within three structural domains that were constructed incorporating Chesapeake's 2008 drilling data along with older Cambior drill results into an updated geologic interpretation. Block size used was 15 meters by 15 meters by 15 meters with 7.5 meter long drill composites used to minimize smearing. The grade models were validated visually and the resource estimate compared with results using nearest neighbour and ordinary kriging models. Tonnage estimates incorporated 250 specific gravity and bulk density measurements with average densities ranging from 2.05 g/cc to 2.82 g/cc being assigned to eight different rock types. IMC used a special grade kriging, independent of block grade estimation, to classify the blocks into the different confidence classes.
Mineral resources were estimated using a US$750 per ounce gold price and within an optimized pit shell (using a cut-off grade of 0.50 g/t gold equivalent) based on the concept of a large open pit. Measured, indicated and inferred classed material were allowed to contribute to the economics of the cone. The economic parameters and costs used to the develop the cone shell are processing the ore via grinding, production of a flotation concentrate and roasting of the concentrate to produce a calcine which can be treated by cyanidation to recover gold and silver. Assumed operating costs were US$1.15/t for mining, US$7.75/t ore for milling and treatment and US$.50/t ore for general and administration. These assumed costs are based on a mining rate of 60,000 ore tonnes per day. Overall metal recoveries of 85% were assumed for gold and silver. Zinc credits were not included in the economics. These preliminary assumptions for projected costs and recoveries are based on projects of similar production rates and should be considered preliminary and subject to a high degree of uncertainty.
The open pit associated with the reported resources extends about 2,500 meters in a north-south direction, is about 1,700 meters wide and up to about 600 meters in depth. The overall waste to ore stripping ratio is about 1.80. Excellent potential exists to further increase the resource base. The Main Zone remains open along strike to the southeast and the North Zone remains open in both strike directions, northwest and southeast. A recent IP geophysical survey has also identified a large new anomaly consistent with the Main Zone signature situated under cover, 200 meters outside the southeast limit of the Main Zone's known mineralization. In addition, Chesapeake's 2008 drill program demonstrated the disseminated mineralized system extends and has not been fully tested in the 150-200 meter wide corridor between the Main and North Zones.