technical report on the nechalacho deposit, thor lake project ...

ASSAY AND METALLURGICAL LAB
The mine, when operating at 1,000 tpd is expected to generate about 20 samples per shift for
analysis, or 40 samples per day, with four from the each working face. In addition, there may be
a further 10 or 20 samples of various kinds such as muck samples, low grade stockpile
samples, etc. These rock samples will be prepared in an area shared with the metallurgical
laboratory and described below.
The flotation plant will produce composite solids samples for each shift from feed, magnetic
tailings, slimes tailings, four flotation products, and gravity tailings. Additionally, each product
container will be sampled meaning about eight product samples per day in the initial years. In
total there will initially be 24 solid samples per day rising to 32 samples per day. In addition to
the analytical work on the solids, eight samples will be processed for screen analyses on a daily
basis in the metallurgical laboratory.
All solution samples will be sent to the ALS Laboratory in Yellowknife, or a similar organization,
for analysis.
Slurry samples will be filtered in the mill and wet filter cakes, and solution where appropriate,
delivered to the sample preparation area at the end of each shift.
Mine and mill samples will be initially dried in a large oven. High grade samples, such as
concentrate will be processed in a separate drying oven. Coarse samples will then be crushed
to -10 mesh and finally pulverized to 100% passing 100 mesh. High grade samples will be
batch processed through the same equipment following a thorough cleaning with sand.
A 10 g sample of pulverized material will be split for assaying.
Solid samples will be analysed using an INNOV-X X-5000 mobile XRF unit. It is estimated
that 100 samples can be processed in a 10 hr shift. Two X-5000 machines will be required in
order to maintain sufficient productivity and for backup.
QA/QC standards will be developed for the laboratory including protocols for duplicates and for
external checks.
The sample preparation and assay laboratory will require the services of a Chief Assayer, two
sample preparation technicians and an assayer for a total of four. Two such crews would be
needed, one on site and one on a rest period.
A metallurgical laboratory at Thor Lake will be used to prepare and test samples as part of
monitoring and improving the performance of the flotation mill.
Technical Report 43-101 – March 13, 2011 Page 18-41
Prepared by Avalon Rare Metals Inc.