EXPLORATION / DEVELOPMENT

Discovery Silver test work streamlines Cordero

A prefeasibility study metallurgical test programme on Discovery Silver’s Cordero silver project in Mexico has returned sulphide recoveries higher than assumptions made in the preliminary economic assessment, ranging around 85-95% at an “extremely course” grind size of about 210 micron, the company said.

 Discovery's Cordero

Discovery's Cordero

"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.

A growing series of reports, each focused on a key discussion point for the mining sector, brought to you by the Mining Journal Intelligence team.

A growing series of reports, each focused on a key discussion point for the mining sector, brought to you by the Mining Journal Intelligence team.

editions

Mining Journal Intelligence Investor Sentiment Report 2024

Survey revealing the plans, priorities, and preferences of 120+ mining investors and their expectations for the sector in 2024.

editions

Q1 Mining Equities Report 2023

Discover new trends in mining investment with insights into capital raisings and share price performance of more than 2,500 companies.

editions

Mining Journal Intelligence Mining Equities Report 2023

Access an exclusive, inside look on the quarterly mining IPOs and secondary raisings data and mining equities performance tables with an annual Stock Exchange Comparisons supplement.

editions

Mining Journal Intelligence World Risk Report 2023 (feat. MineHutte ratings)

A detailed analysis of mining investment risks across 121 jurisdictions globally, built on 11 ‘hard risk’ metrics and an industrywide survey.