Equitas Resources Corp. (EQT.V) reports on positive metallurgical testing from the Baldo zone at its Cajueiro gold project
– Momentum Public Relations –
Press Release: August 18, 2016
Equitas Resources Corp. has released positive metallurgical test results from the Baldo zone of its 100-per-cent-owned Cajueiro gold project in central Brazil.
Major highlights include:
Results indicate gold recoveries of 93.7% to 96.2% are possible using conventional Carbon-In-Leach (“CIL”) technology for saprolite oxide mineralization at Baldo, in contrast to the lower than expected recoveries from gravity methods. Decision to fast track straight to the CIL process, which shows higher recovery levels than initially planned for. An engineering firm with extensive experience of gold processing in Brazil is being engaged to complete detailed analysis and design of a planned 250-400 tonnes per day (“tpd”) CIL test plant. Extraction permits are in place for 50,000 tonnes per annum (“tpa”) of material from each of the Baldo and Crente bulk sampling licenses (in Portuguese – “GUIA” or Guia de Utilizacion).
A 118 kg composite sample of gold-mineralized saprolite identified by the recently reported trench assays was sent to Testwork Desenvolvimento de Processo Ltda (“Testwork”) in Nova Lima, Minas Gerais State, Brazil for bench-scale metallurgical testing, including comminution, gravity separation and cyanide leach via bottle roll tests. The Testwork report indicates recoveries of up to 96.2% were possible using conventional cyanidation methods. Gravity concentration tests indicated only very poor recoveries are possible with this method, up to a maximum of 22.1%. The tests highlighted the presence of fine gold and the importance of grind size and cyanide leach residence time in the gold recovery process.
Test Direct Leaching Sample Type AF Head AF Head Sample Number LT1 LT2 P80 Feed Size 106microm 75microm Au Head avg. Assay g/t 5.19 5.19 Au Head Calculated g/t 5.42 5.27 NaCN Initial g/t 1000 1000 NaCN Consumed g/t 179 375 Leach Time (Hours) Tails g/t Au Recovery% Tails g/t Au Recovery % 2 53.8 48.1 4 71.4 70.5 8 82.9 84.7 24 0.42 93.7 0.28 96.2
Testwork Technical Director, metallurgist Mr. Walter Moura, M.Sc., AusIMM, concludes the following:
The mineralised material is “free milling”, that is, the gold is liberated and accessible for cyanide leaching without requiring specific pre-treatment The gold is generally fine, with best leaching results for a P80 grind size of 75mum. Ferrocyanide compounds were not formed during leaching, indicating that the mineralisation does not contain cyanide-consuming minerals and that pre-treatment with lime is not likely to be required. The test results support a direct cyanidation approach to gold recovery
It is now clear to the Company that the CIL process is the most effective choice (as regards recoverability and economics) for beneficiation of the mineralized saprolite oxide at Cajueiro. We have decided accordingly to fast-track straight to the CIL plant as a first phase and not develop the initial gravity plant. This CIL plant will then be rapidly expanded following the first development as the current resource base continues to be evaluated and expanded. An engineering firm is being engaged to complete detailed analysis and design of a 250-400 tpd capacity CIL test plant. Site design work has been initiated including a topographic survey. Amendment to the environmental permits will be sought as soon as the plant and mine design work is concluded. This is expected to be a fairly rapid process. Build process should start in Q4 2016 and take approximately 6 months to completion.
Baldo and Crente Saprolite Inferred Resources
The Baldo and Crente GUIA’s allow for extraction in total of up to 100,000 tpa of material for bulk sampling purposes. If fully utilized this would result in excess of 12,000oz per annum gold recovered through a typical CIL plant, given recovery levels indicated by the metallurgical testing. Current Inferred Resources (saprolite oxide) for Baldo are 309,000 tonnes @ 3.029 g/t Au, and Inferred Resources (saprolite oxide) at Crente amount to 381,000 tonnes @ 1.482 g/t Au (Gustavson Associates, 2016).
Commenting on the results of the metallurgical testing, President and CEO Chris Harris stated “I am highly encouraged by Testwork’s positive analysis of the cyanide leach testing, signalling that high gold recoveries can be obtained with limited grinding, rapid leach times and low reagent consumptions. This is strongly supportive of our planned plant development. We are engaging Testwork to provide design and engineering services to finalise design and support implementation of a CIL test plant to treat up to 100,000 tpa of bulk sample material from two licences already permitted. Construction of this facility is anticipated to commence in Q4 2016”.
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NI 43-101 Disclosure
Everett Makela, P. Geo., VP Exploration for Equitas Resources Corp., a Qualified Person as defined by National Instrument 43-101, has reviewed and approves the technical information in this news release.
For more information on Equitas Resources Corp., please contact Sean Kingsley, Corporate Communications at 604-681-1568 or email@example.com.