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 | 60
13.7 Drill holes results, 2012 REE exploration program.
The 2012 exploration and definition drilling program confirmed the REE mineralisation
distribution homogeneity. The 100 x 100 metres drilling mesh performed help the geology
team to define the core of the REE rich carbonatite and the relationship with the surrounding
units. The transition zone returned interesting results on large interval and must be evaluated
for it economic value.
The new 100m x 100m drilling pattern increased the resource confidence from sub-surface to
350m below. The 2011 inferred resources were all transformed in indicated resources. The
drilling accuracy from 350m to 700m, 100m x 200m drilling mesh, added inferred resources
at depth. Even if the resources calculation was limited to 700m, the deepest holes confirmed
the mineralisation continuity down to 1200m below surface.
Mineralogical studies are under progress to evaluate the REEs mineral affinities and
distribution. The 2012 drill hole reached deeper than ever historically. Preliminary
interpretation based on the core description and the Assays results show a relationship
between the REEs mineral content and the deepness. Pass 1000m deep, the texture of the
hosting carbonatite and the lanthanide minerals change. Simultaneously, the average REE
content slightly increased. This observation are currently investigated and tested by a master
project conjointly realised by IAMGOLD-Niobec and the UQAC University.
The deep holes also tested gravimetric anomaly hypothesis. In 2011, based on theory
projection, an ultra-mafic source, located at the base of the Saint-Honoré carbonatite
complex, was interpreted to be the explanation of the gravimetric anomaly. Excepted few
angular enclaves of mafic to ultra-mafic rock intercepted by drilling and observed in the drift,
no major units was discovered. The ultra-mafic basement theory may be transferred to a
lower level. The geophysics interpretations plan the anomaly around 500m deep. This may
be explained by the vertical distribution of the barium. From the surface and down to 200m,
the barium is completely depleted. Assays are returning value under the limit detection.
Abruptly, the average barium contain rise above 3%, higher than all the other carbonatite
facies of the complex. The phenomenon is also slightly observed in the rock density..
Over all, the 2012 drilling exploration program returned excellent results and a lot of new
geological data that will be interpreted in 2013. Each drill hole results are summarised in
Table 7 below.
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