Laterite Leach Tests

ANSTO Minerals Report C1206 to Lagoon Creek Resources – Westmoreland Deposits
The size by size analysis of each composite sample indicated that uranium was uniformly
distributed in each size fraction, in proportion to the sample mass distribution with a slight
tendency for uranium minerals to report to the finest fraction. Therefore, the ore could not be
upgraded based on size separation.
3.5 Grind Calibration Curve
Grinding assessment tests were carried out on the composites from the Redtree and
Junnagunna deposits in a batch rod mill on 1 kg samples with 10 rods to produce grind
response curves that will allow the time required to produce a target P80 grind size for the
crushed ore materials.
All grinding tests were carried out in Sydney tap water. Grind size distributions were
determined by wet screening at 38 µm and dry screening the oversize at 600 to 45 µm. A wide
spread of grind sizes was targeted, as follows:
P80 = 350 µm
P80 = 250 µm
P80 = 150 µm
P80 = 75 µm
The size fractions from the coarsest grinds of the Redtree and Junnagunna composites were
analysed for U by DNA and by XRF for the same suite of elements as described in
Section 3.2. Ore samples were milled in Sydney tap water in preparation for leaching to
achieve a specified P80 grind size. The trial grinding tests results are summarised in Tables
3.10 and 3.11. Particle size distribution (PSD) curves from the grinding assessment testwork
are shown in Figures 3.6 and 3.7.
TABLE 3.10
Summary of Trial Grinding Results - Junnagunna Lens
Cumulative wt% Passing
Size (µm) 3 mins 10 mins 14 mins 20 mins 60 mins
600 93.8 100.0 100.0 100.0 100.0
425 75.1 99.9 100.0 100.0 100.0
300 53.8 94.0 99.2 100.0 100.0
212 38.5 70.7 86.0 97.3 100.0
150 30.0 54.1 67.2 82.3 100.0
106 22.4 40.0 49.8 61.8 99.1
75 17.6 30.5 37.2 45.5 89.5
53 13.9 23.3 28.0 33.5 68.3
45 12.2 20.5 24.6 29.3 60.0
38 10.9 17.9 21.2 25.1 51.8
11