NI 43-101 Technical report, Surface diamond drilling ... - Iamgold

R a r e E a r t h E l e m e n t E x p l o r a t i o n P r o g r a m M a r c h - 2 0 1 3
W i n t e r - S u m m e r 2 0 1 2 P a g e | 100
• Calculate and model the major, semi-major and minor axes of continuity.
The anisotropy direction was determined using the regressions rules in “SAGE” software.
The variogram was modeled with a nugget effect and two structures representing the larger
scale spatial variability of the datasets. The modeled correlogram is summarized in Table 20.
The rotation angles use the Gemcom convention around the ZYZ axes based on the
orientation of the block model.
The set of rules would be the same for all REO as for TREO except the limits on grade for
the Top Cut Value and the Cut-Over High Grade Value would have to be adjusted
accordingly.
Table 20: Variography statistics
Ranges (m) Rotation (°)
Element Nugget effect 1 st Structure 2 nd Structure Z X Z
X:50 X:750
TREO (%) 0.422
Y:150 Y:360
Z:360 Z:700
0 0 0
Sill:0.431 Sill:0.147
19.1.2 Domain and Volume
The REE Zone mineral resources model is limited to the core of the Saint-Honoré carbonatite
complex. The C1 rock type is (the REEs mineralized carbonatite) containing the majority of
the mineralization but a surrounding crown, called the transition zone, included the low grade
values. The transition zone is formed of mineralized C1 injected in the C2 (massive
carbonatite) and the S1 (syenite). The geological model outlying the REE host rock was
drawn in 2011. A vertical projection was drawn from the surface compilation map (Figure 5)
using a 70° dip cone shape truncated first at 1000m depth in 2011 and extend at 1400m depth
in 2012 (Figure 26). The volume is adjusted to the drill hole rock type description and assay
values to obtain a 3D cone shape confining the grade interpolation process.
The geological model will be reviewed in 2013 with all the new data collected by drilling in
2012. The core zone and the transition zone will be separated for a better definition of the
resource. However the geological model is not up to date, the 2011 model is judged enough
close to the reality to use it for generating a valid resource interpolation.
3400, chemin du Columbium, St-Honoré-de-Chicoutimi, QC G0V 1L0 Canada – tel. : 418 673-4694 Fax : 418 673-3179
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