March 4, 2013
/PRNewswire/ - MAX Resource Corp.
(TSXV: MXR); (OTCBB: MXROF); (Frankfurt: M1D)
has received the preliminary report by
, P.Eng., Consulting Metallurgical Engineer of Laurion Consulting Inc. on the test work carried out on samples from it's wholly-owned Majuba Hill copper/silver project in
by Inspectorate Exploration & Mining Services in
A total of fourteen samples of assay sample reject material (crushed to 6 mesh) were received at Inspectorate and these were made into a single composite weighing 58 kg. A sub sample was taken for head analysis and indicated a grade of 0.62% Cu and 34.6 g/t Ag.
A series of bottle roll acid tests were carried out with sulphuric acid at pH 1.3 on material running 6 mesh and on material ground to 200 mesh.
After 14 days of leaching the copper extraction was 81.1% and 84.6% respectively
. These results indicate the potential for heap leaching copper in a relatively short leach cycle, with acid consumption modest at 25kg/t, which is in line with expectations.
Leach testing was also conducted with thiosulphate over a six hour period and 24 hour period. Leaching was carried out at pH8 on the two samples, 6 mesh (un-ground) and 200 mesh.
Silver extraction of 73.4% was achieved
on ground material, which was 30% higher than on un-ground material. Thiosulphate leaching is normally very rapid; the difference between ground and un-ground leach recoveries may disappear over a longer leach cycle. Moreover, the silver leach value has not been optimized and it is expected that silver recovery may increase with longer leach times.
While cyanide leaching of sulfuric acid leach residue was also undertaken and gave about a 70% recovery, the thiosulphate leach route may be preferred because of reduced reagent costs (less lime required to neutralize acid to pH8 rather than pH10, and less consumption of lixivient as thiosulphate is not consumed leaching excess copper) as well as for environmental considerations.