Scoping flotation tests were conducted on both of the composite samples at a grind size of 72 to 74 microns. Both Pepas #1 and Pepas #2 were highly amenable to scoping flotation tests, achieving gold recoveries of 87.9% Au and 75.3% Ag in 11.4% mass yield, and 95% Au and Ag in 20.6% mass yield respectively.
2. CENTRIFUGAL GRAVITY CONCENTRATION
Feeds were grounded to four target sizes ranging from 71 to 194 microns and were processed through the gravity concentrator three times to determine the amount of free milling gold that can be recovered by gravity. Panning to stimulate cleaning by a shaking table was utilized to further upgrade each gravity concentrate. Au recoveries on Pepas #1 ranged from 51.9 to 61.6% and on Pepas #2 from 42.1 to 50.2%.
3. CYANIDE LEACHING
Cyanide leach tests were conducted on four grind sizes ranging from 71 to 194 microns and were leached for 48 hours (except for one test which was 72 hours) by bottle roll at a pH 10.5 and Sodium Cyanide (NaCN) concentration of 1.0 (except for one test which used an NaCN concentration of 5.0 g/L) After 48 hours gold recoveries for Pepas #1 ranged from 87.6 to 90.7 and for Pepas #2 from 40.5 to 67.6%. After 72 hours the Au recover increased to 70.4% for one test.
This initial range of test work suggests that the gold has a strong association with sulphides, possibly allowing a wide range of concentration and processing alternatives to optimise recovery. Both the Pepas #1 and Pepas #2 samples responded well to flotation (recovering 87%+ of Au), while more than 42% of the gold in the samples was recoverable by gravity concentration methods. The results of the cyanide leach tests of the higher grade (26 g/t) Pepas #2 sample, relative to Pepas #1, suggest that additional work is required to understand the metallurgy of the sulphide mineralisation and to optimise key parameters including grind size and leach time. Such test work and flow sheet development will aid in the optimization of gold recoveries utilizing flotation, gravity and cyanide leaching processes.
The deposit in the Rio Pescado property of the Segovia Gold Project has a drill tested strike length of 800 metres by a vertical depth of 100 metres. To date, the Company has drilled over 15,000 metres in 193 drill holes at the Rio Pescado property to date. The deposit is currently open down-dip to the west, along strike to the south and at depth. The first phase of a 15,000-metre diamond drill program is currently underway to conduct infill, step out and exploration drilling at the Company's previously identified and newly discovered target zones within the project.
The first assay results from Touchstone's current drill program are expected to be received in April 2013.
John Nicholson, Chief Geologist of Touchstone Gold Limited, is a qualified person as defined by National Instrument 43-101 and prepared or reviewed the preparation of the scientific and technical information in this news release with respect to the assay results from the drilling program. Mr. Nicholson has a B.Sc. from the University of British Columbia, is a Fellow of the Royal Geographical Society and has been an accredited member of the Association of Professional Engineers and Geoscientists since 1992. Mr. Nicholson has verified the data disclosed in this release, including the sampling, analytical and test data underlying the information presented. Verification included a review and validation of the applicable assay databases and reviews of assay certificates.
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