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 | 112
Item 22. RECOMMENDATIONS
22.1 Geological compilation and resources modelling.
The new geological information collected during the 2012 drilling program was not totally
interpreted. The REE zone contacts were frequently intercepted, especially at depth, and an
update of the geological model is needed. In the Saint-Honoré carbonatite complex context,
the 2011 geological model (Lafleur, P.J., 2012) contained enough detail to update the TREO
resources without any doubt on the reliability of the results. By modeling the transition zone
(“low grade zone”) and the REE core zone (“high grade zone”) a grade interpolation could be
applied individually to those new geological volumes. The expected results on the resources
model will be an increasing of the TREO concentration coupled with a decreasing of the
tonnage in the core zone. With cumulative mineral inventory of over 1 billion tonnes,
decreasing the tonnage won’t have a negative aspect compared to the benefit of increasing the
concentration.
The specific gravity used for the 2012 block model included the 2011 back ground value for
the carbonatite of 2.86 t/m 3 . Basic statistics made over the new available density data base
returned an average value for the carbonatite of 3.11 t/m 3 . This change must be studied. An
increasing amount of barite is noted at depth and must necessarily affect the density. A
density distribution pattern, within different geological domain or inside one domain, must be
integrated to the next geological interpretation and blocks model.
The TREO value is a composite of 14 individual rare earth elements values added together.
A proportion relationship between each element was established by P.J. Lafleur. Base on this
information only the TREO attribute was calculated for the 2012 block model. The statistic
and the variography of each element should be added for validation or comparisons.
22.2 Mineralogical characterisation and metallurgy.
A Mineralogical study is ongoing. The petrographic, the geochemical and the mineralization
characterisation of the REE zone at depth, under 500 metres below surface, are the objects of
a master project. Preliminary report should be produced to help the geological modeling and
metallurgical test works. A synergy between geological improvement and metallurgical
testing would be benefit to the REE project.
The hyper spectral technology might help the geological team to build a homogeneous data
base to improve the actual geological model. Even if the traditional core logging description
seems to work for outlying the core zone, the spectral technology can precisely evaluated the
REE mineral concentration and nature especially in the brecciated facies where the
granulometry become smaller. It is recommended to test the benefit of the hyper spectral
technology by building the library with the entire representative and available core.
3400, chemin du Columbium, St-Honoré-de-Chicoutimi, QC G0V 1L0 Canada – tel. : 418 673-4694 Fax : 418 673-3179
E-mail : info.niobec@iamgold.com www.niobec.com