Paris was estimated at 42 million ounces and 55,000 tonnes lead in 2017 using a 50 gram per tonne cut-off based on a A$22/oz silver price, and after a significant investment in drilling over the past year has been re-estimated at 53.1Moz silver and 97,600t lead using a cut-off of 30gpt silver, based on a $35/oz silver price.

 

Resource tonnage was up 100% to 18.8 million tonnes, but the grade fell 37%, although contained silver increased by 27% with the lower cut-off.

 

Around 73% of the resource is now in the higher confidence indicated category.

 

Managing director Andrew McIlwain said the decision to lower the cut-off to the level that was used for the maiden resource in 2013 was appropriate given the significantly higher silver price, which was US$26/oz on Friday.

 

However, running the numbers using the 50gpt cut-off leads to a substantially unchanged 42Moz at an average grade of 133 parts per million silver, a slightly lower resource grade despite some stunning intercepts in recent months, such as 1m at 8210 grams per tonne within a broader 19m at 561gpt from 55m, which had created anticipation of a boost in grade.

 

McIlwain said that while the infill drilling across Paris in 2020 may not have substantially boosted contained silver, it had boosted tonnage and had improved the level of confidence in the deposit.

 

He said the economics of Paris had substantially changed. 

 

A pending prefeasibility study will examine a 10-year mine life, while offering opportunities for improved efficiencies, supporting alternate considerations for infrastructure and renewable power supply options, and financing partners. 

 

Work has started on mine design, planning and scheduling, with process plant design and capital estimation well advanced.

 

Earlier this month metallurgical tests improved recoveries from 65% to 72%.

 

The PFS is due for release next quarter.

 

Paris is described as a shallow, high-grade, open pit mine, with the deposit striking up to 1600m, down to about 130m. 

 

The deposit is highly sensitive to metal prices, and Investigator believes it can improve the outlook if it can reduce operating and capital costs, or if the silver price improves. 

 

Further drilling is planned to develop a maiden reserves statement, to help support a definitive feasibility study.

 

The Gawler Craton project was discovered in 2011 and is described by Investigator as the highest-grade undeveloped primary silver project in Australia. 

 

The company started the quarter with around A$12 million.

 

Shares in Investigator dipped 2% today to 8.8c, valuing it at $119 million.

 

The stock has traded between 1.6-12c over the past year.