El Zorro exploration work. Source: Tesoro Resources
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  • Tesoro Resources (ASX:TSO) announces “first-class” results from a recent second-phase metallurgical testwork programme taken on at its El Zorro Gold Project in Chile
  • The company says the phase two test work demonstrated “rapid” leach times, with most tests achieving gold extraction in excess of 90 per cent within eight hours
  • The test work indicated achievable gravity recovery of 45 per cent and overall recovery of 94.5 per cent at 150 microns and up to 98 per cent at finer grind sizes
  • Tesoro says the results from its testwork will be used to set the process design criteria for the Ternera gold deposit in the project area
  • Shares in Tesoro Resources are trading grey at 8 cents each at 10:46 am AEDT

Tesoro Resources (TSO) has today announced “first-class” results from a recent second-phase metallurgical testwork programme taken on at its El Zorro Gold Project in Chile.

The junior explorer said the phase two test work demonstrated “rapid” leach times, with most tests achieving gold extraction in excess of 90 per cent within eight hours.

The tests were designed to evaluate the gravity recovered gold component and cyanide leaching characteristics for a range of gold samples taken from the El Zorro project.

Tesoro said it tested 529 kilograms of samples from various mineralised zones at the project using different grind sizes to determine which size will work best for future processing.

The test work indicated achievable gravity recovery of 45 per cent and overall recovery of 94.5 per cent at 150 microns and up to 98 per cent at finer grind sizes. One micron is equivalent to a millionth of a metre.

“These are first-class metallurgical results confirming high gravity and cyanide leach recoveries that can be achieved for processing material from Ternera using conventional gravity and carbon-in-leach (CIL) processes at coarse grind sizes,” Tesoro Managing Director Zeff Reeves said.

“These results have enabled the development of a very simple, generic, preliminary processing flowsheet and largely de-risks one of the project’s key revenue drivers as it advances toward development.”

Tesoro said thanks to the testwork, it was able to determine the optimal processing method for recovering gold from the Ternera gold deposit in the project area.

This process includes a bond ball mill work index of 20.4-kilowatt-hours per tonne, a leach feed grind size distribution of 150 microns, and cyanide consumptions of 0.5 grams per tonne.

Tesoro said the results from its testwork will be used to set the process design criteria for Tenera.

Shares in Tesoro Resources were trading grey at 8 cents each at 11:36 am AEDT. The company has a $52.3 million market cap.

TSO by the numbers
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