RE: RNS OUT12 May 2020 08:47
Part of the RNS....
Initial flotation tests on Batch 2 samples returned the following,
Sample 4 produced a concentrate grading 26.6% copper at an 84.8% copper recovery
Sample 5 produced a concentrate grading 20.0% with a 94.6% copper recovery and a 92.5% molybdenum recovery.
Sample 6 recovered a bulk concentrate grading 28% copper, 14% zinc and 2.8% lead with recoveries of 91% for copper, 94% for zinc, 83% for lead and 89% for molybdenum.
Of great interest is the confirmation of the historical metallurgical results as derived from historical mine records. Specifically, for the copper concentrate, the historical recovery of copper into the copper concentrate for the period 1999 – 2009 was 85.5% with concentrate grading 28.2% copper.
Of note also from the historical processing records, a gold flotation recovery of 75.9% and a silver flotation recovery of 47.3% was achieved into the copper concentrate. Processing records for gold and silver are present for the period 1999 – 2003 which indicate an average feed grade of 0.38g/t gold and 48.3g/t silver for this period.
The higher gold and silver values reported in the head assays for sample 1 – 6 offer confirmation to the results from the underground sampling conducted in 2011 and 2012. These historic underground samples have not been used before in any of the Company’s estimations as they have been unable to have their spatial position verified to an acceptable degree of certainty. These new results now provide Vast with increased insight into the expected gold and silver values in the working areas expected to commence production shortly and would substantially increase the value of the saleable copper concentrate.
Test work by Grinding Solutions under the guidance of Minxcon based out in South Africa is continuing with the view to providing a cost effective and efficient means of producing the three independent concentrates, copper, lead and zinc.
The Company is extremely pleased with the initial indications from the test work on producing the copper concentrate and so far, the grades are greater than originally forecasted. It is expected that the underground drilling currently underway will further confirm the continuation of similar grades at depth.
The Company looks forward to providing updates on the continuing drilling and assay results over the next 4-6 weeks