"In addition, our first ever flotation test work of an oxide-sulphide blend returned very positive results with economic recoveries for oxide mineralisation for silver, lead and zinc through flotation," the company's interim CEO Tony Makuch said.
Silver recoveries stood at 94-98%, lead at 89-97%, and zinc at 92-96% on high grade samples of all major rock types.
From medium grade samples of blended rock types, the results saw silver recoveries of 83-92%, lead of 85-92%, and zinc recoveries of 81-89%.
Oxide-sulphide beldn test work established oxide-specific recoveries of about 60% for silver, 40% for lead, and 85% for zinc via flotation.
"These results allow for the elimination of the heap leach circuit in our PFS; this will streamline the crushing/grinding circuit, reduced upfront capital expenditures and simplify the permitting process," he said.
The 2021 PEA for Cordero viewed a base case after-tax NPV5% of US$1.2 billion and IRR of 38%.
The payback period was two years, using base case prices of $22/oz silver, $1,600/oz gold, $1/lbs lead, and $1.20/lb zinc.
The PEA viewed a 16-year mine life with average annual production of 26 million oz AgEq at an AISC of $12.35/oz AgEq and an initial development capital expenditure of $358 million.
Discovery notes that the project is close to infrastructure in the state of Chihuahua.
The company had a share price of C$1 (US$0.77) on 29 August, with a market capitalisation of C$349.02 million.
