Aura upbeat on preliminary gravity survey results

Aura Energy announced preliminary results of the first of the planned gravity field surveys on its Tasiast South tenements on Thursday.

The AIM-traded firm also said water drilling was underway at Tiris, adding that it was confident that the programme would continue the previous results from water drilling undertaken in 2019.

It said that, to undertake the gravity survey, two geophysical crews from gravity specialist GeoFocus were mobilised from South Africa to carry out detailed gravity surveying on all three of Aura's tenements at Tasiast South.

In total, 6,643 stations were surveyed, with the programme specifications designed and activities overseen by Newexco - geophysical consultants based in Perth with “extensive” experience in Archean geophysics.

The gravity data would allow better definition of geology, the identification of structures likely to be of relevance to gold deposition, and the possibility of direct detection of sulphide mineralisation on the nickel-cobalt targets.

Aura said the northernmost tenement, Nomads JV, where it is earning a 70% interest, had no meaningful exploration despite it covering 50 square kilometres of Archean greenstone belt located 35 kilometres directly along strike from Kinross' giant 20 million ounce Tasiast Gold Mine, which was currently being mined at a rate of 400,000 ounces of gold per year.

The area was one of “almost no outcrop”, with the gravity survey expected to define the greenstone belt, lithologies and structures permitting the planning of follow-up bedrock sampling and deeper drilling.

Newexco reported that the survey data met specifications and was fit for purpose, with processing and analysis currently underway.

The data from the completed survey would be used to complete an enhanced interpretation of geology, structure and their relation to mineralisation using all existing data including airborne magnetics and drillhole data.

Aira said the field data indicated four localised gravity anomalies, all on ultramafics on the Bella permit, which was of potential interest from the viewpoint of nickel sulphide mineralisation, although that would only be determined by drilling.

Infill gravity surveying was carried out on those targets.

The company maintained that the tenements, with the single large Tasiast gold mine along strike, and strong base and battery metal results from limited previous exploration, represented “some of the best” under-explored greenstone belt targets in the world.

“It is a very important step to complete the first planned field survey on Tasiast South, as it helps build the maps towards targeting and discovery,” said managing director Peter Reeve.

“The gravity survey provides valuable data which will guide future exploration, as we continue to advance this highly underexplored project, which represents some of the best greenstone belt targets in the world.”

At 1400 BST, shares in Aura Energy were down 0.95% at 5.2p.