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 | 75
Item 16. DATA VERIFICATION
16.1 Verification with laboratory certificates
IAMGOLD-Niobec geological team was receiving electronic Laboratory certificates
during the entire program. They were verified and numerically archived on the
informatics mine system. SGS also kept a certificate version on their SLIM program.
They are available at all time.
In 2012, the Lablogger software from Gems was used to import the certificate into the
Gems data base. The data manipulations were restricted and the probability of error
decreased. By referring to only one laboratory, SGS, the certificate presentation were
standardized and constant all year long.
Lablogger is also used for the QA / QC program.
16.2 QA / QC program
IAMGOLD carried out a QA/QC program with blanks samples, 3 certified REE
standards samples (low, medium and high grade) and core duplicates (discussed in Item
14). This is without mentioning the laboratories own check assays and duplicates. Small
anomalies were found through the year and were immediately signaled and corrected by
SGS. Re-assayed was realised when necessary. A large number of elements, 15 for REE
plus numerous associated elements (Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sm, Tb, Tm,
Yb, Y, Sc, Nb, U, Th,…), were involved in the QA / QC program but only the four
majors REE elements are presented as director line.
16.2.1 Blank sample results and interpretation
The blank sample, which is not a certified commercial blank, is not truly blank. It has a
very low average grade of 119 ppm TREE (Table 8) and a relatively high coefficient of
variation. The blanks were used 331 times (Table 11) to check the SGS laboratory
samples preparation protocol. The TREE averaged valued is 179 ppm and varied from
107 ppm to 334 ppm during the year (Table 12). The coefficient of variation seems to
increase with the volume of samples processed in a month. However the average TREE
value can reach almost twice the value of the original “blank” sample, those values still
very low and near the TREE background limit. Looking at the lanthanum values (Figure
22 and Table 12), the highest level of contamination noticed is 0.06% La (600 ppm).
Even if a correction measures was taken in this case, the 0.06% La contamination is very
low compared to the 0.4% La mean value for all 2012 samples.
The outliers limits were placed very low for all REEs. In Table 12, the cerium had an all
year bad performance with 27% of the sample being above the 100 ppm Ce imposed
limit. Once again, even the highest level of Ce contamination (near 1200ppm) is
considered marginal compared to the Ce high average value returned in the REE zone.
The high variability of the blank samples was not considered problematic for the data
base validity.
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