E2 Metals (ASX: E2M) reported promising metallurgical results on its Mia gold-silver prospect in Argentina with a recovery rate of over 90% gold using conventional bottle roll testing. cyanide.
Test work was performed in Santiago, Chile, on composite samples of drill holes in oxide, transition and sulphide mineralization.
High gold recoveries were obtained at both fine and coarse grind sizes.
E2 Metals added that cyanide consumption during testing was “generally low”.
Silver mineralization also lends itself to recovery
In addition, the silver mineralogy identified as electrum and acanthite (a silver sulfide) has been shown to be suitable for both cyanide leaching and gravity recovery.
Mia is part of the company Conserrat Project, which includes a single title of 8,696 hectares in the province of Santa Cruz in Argentina.
The title is centered 130 km northwest of local service town Puerto San Julian and approximately 30 km west-northwest of AngloGold Ashanti’s large Cerro Vanguardia mine (ASX: AGG).
Cerro Vanguardia is the largest epithermal vein field in the province of Santa Cruz with historical and current resources estimated at 8.9 million ounces of gold and 137 Moz of silver.
The test work will now expand to other prospects
E2 Metals chief executive Todd Williams said more studies are planned that will examine silver recoveries via gravity concentration and cyanidation.
He was optimistic about the first round of gold recovery tests.
“These preliminary metallurgical results are encouraging and show that the oxide mineralization at Mia is free and lends itself to a simple heap leach operation.”
Williams added that metallurgical testing will continue alongside the ongoing exploration drilling program and that the company will expand metallurgical testing work to samples from other prospects.
Shallower depths tend to be predominantly silver
Silver recovery was not a primary target for this phase of the metallurgical test work.
“Instead, a greater emphasis was placed on understanding the mineralogy and behavior of silver to enable the development of targeted programs in future stages of the work.”
On gold testing, the company states that gold mineralization is best developed in the oxidized parts of the Lara vein structure at Mia.
The deeper sulphide mineralization tends to be silver dominant, and gold grades range from 0.5 grams per tonne to 1 g / t.
In the oxidized section, the metered gold returned 2.9g / t (with 381g / t silver).