Investigator Resources shows conventional processing route at Paris Project
Investigator Resources (ASX: IVR)
has completed metallurgical trials indicating that mineralisation from
the Paris Silver Project in South Australia is amenable to conventional
processing.
The tests returned initial silver recoveries of
between 65% and 97% from a range of samples that represent a majority of
the Paris deposit.
Flotation trials were successful in producing
a rougher concentrate of 1,405 grams per tonne silver, which is in the
acceptable range for smelter sale, however this is likely to be further
upgraded with cleaning.
Further increase in silver recovery are expected by optimisation with standard leach and/or flotation techniques.
“We
are very encouraged with the first-pass metallurgical results that
indicate the Paris silver mineralisation is likely to be amenable to
conventional extraction processes,” managing director John Anderson
said.
“This adds confidence to the Paris silver project for which
a maiden resource was announced last week containing 20 million ounces
of silver at 110 grams per tonne silver and 0.6% lead using a 30g/t
silver cut-off.
“These initial metallurgical results add to the
positive attributes of the grade, shallowness and open extent for the
Paris silver project. More metallurgical work will be scheduled at the
appropriate time in 2014. This is expected to achieve even better
recoveries through optimisation of the processing pathway.” Mr Anderson
added.
The next phase of metallurgical investigations, expected
to be scheduled in 2014, will look at ways to improve the recovery of
the silver and also to recover the lead. Lead recoveries have not been
considered as part of the initial test work program.
Metallurgical Study
This
initial metallurgical study was designed to characterise and understand
the Paris silver mineralisation, identify any potential metallurgical
issues and support the recently announced Paris Silver Project Resource.
Seven
metallurgical samples were selected as representative of mineralised
rock-types and grade ranges from areas within the resource enveloped.
These were drummed according to procedures provide by the Core Resources Group and sent to their laboratories in Brisbane.
A series of tests were conducted as part of the grind analysis. No potential problems were identified for the grind circuit.
The
final test on material behaviour showed that all samples were sticky
due to high clay content which would impact on slurry viscosity in the
processing plant.
A series of standard cyanide leach bottle roll
tests were positive and indicated that the Paris mineralisation is
generally not complex or refractory. Recoveries increased with the
longer leach time.
Cyanide consumption was low to moderate with the moderate levels in samples with elevated base metals.
Further work may remove the base metals via flotation ahead of cyanidation.
In
addition, the difference between the 24-hour test and the 48-hour test
for silver recoveries indicates a longer leach time would likely give an
even better recovery.
Paris Silver Project
The Paris Silver Project has an Inferred Resource of 20 million ounces of contained silver and 38,000 tonnes of lead.
Notably,
the untested lateral extensions to the drilled resource area offer
opportunities to expand this Resource, which is located at a potentially
open-pittable depth.
Silver Demand
Silver
is the ideal industrial material, with no other metal having its
combined strength, malleability and ductility, or facilitates electrical
and thermal conductivity as well, or can reflect light and endure such
extreme temperature changes, according to The Silver Institute.
Jet
engines depend on silver-coated bearings for their performance and
safety, with all jet engine manufacturers utilising these
high-performance silver bearings which provide critical fail-safe
lubrication.
Silver is also used in the treatment of burns, where
its unique bacteria-fighting qualities forms the basis of silver
sulfadiazine, which is used in every hospital in North America to
promote healing and reduce infection.
Over the last three
decades, global consumption of silver has been higher than it has been
mined, with rising demand and diminishing supply set to provide support
for the silver price.
On a global scale, Mexico is by far the
world's biggest producer with 162.2 million ounces in 2012, followed by
China (117moz), Peru (111moz) and Australia 57 million ounces.
Analysis
With both a Resource and initial metallurgical studies in place, Investigator Resources has built a platform to further expand resources and optimise metallurgical recoveries.
As
noted in its studies, there is considerable scope to further increase
recoveries of silver from the Paris Project while work has yet to be
carried out on recovering lead.
Along with expectations of
growing silver demand, the company is well placed to progress the Paris
Silver Project towards development and production.
