Trigg Minerals reveals promising brine grades ahead of Lake Throssell SOP resource upgrade

Positive drilling results at Trigg Minerals’ (ASX: TMG) Lake Throssell project in Western Australia have confirmed the consistency and robustness of the sulphate of potash (SOP) resource ahead of a resource upgrade later this month.

The explorer today revealed results from 29 brine samples assayed from four air core holes and three monitoring wells within the project.

The potassium grade results range from 4,260 milligrams per litre to 4,970 mg/L, with an average of 4,549 mg/L potassium which is consistent with the low variability of the deposit.

Results from the screened sections of the basal aquifer were between 4,330-4,500 mg/L, consistent with the previous air core results from depth.

Trigg managing director Keren Paterson said this positive result firmly validates the quality, consistency and grade of the Lake Throssell SOP deposit.

“What stands out from the data is the consistency of brine assay results across all of the drilling programs we have completed to date. This bodes extremely well for the quality and consistency of the deposit as a future SOP producer,” she said.

Ms Paterson also noted high-quality data generated from the borehole magnetic resonance geophysical logging has provided the company with “unrivalled” resolution on the key attributes of the deposit that will be “invaluable for a pre-feasibility study in terms of porosity, permeability and lithology”.

“Gaining a firm understanding of these characteristics is essential in proving up a high-quality mineral resource estimate and producing a pre-feasibility study to the highest standard,” she added.

Resource upgrade due this month

Ms Paterson confirmed Trigg’s plans to deliver an upgraded resource update for Lake Throssell later in February.

“It is our expectation that the results will lead to an uplift in the higher confidence indicated resource category,” she said.

“This portion of the resource will, in future be available for conversion to ore reserves as economic studies progress, and we expect will be a key value-driver for the Lake Throssell project,” Ms Paterson added.

Work continued during December quarter

Key achievements during the December quarter included the completion of the resource definition drilling program and the installation of wide-diameter groundwater monitoring bores to facilitate geophysical logging and mini aquifer testing.

A continuous monitoring weather station was installed during the period with satellite telemetry to enable monitoring of local brine evaporation rates, which will be used to inform the design and operation of proposed evaporation ponds and associated infrastructure.

Bulk evaporation trials concluded during the December quarter and all salting phases were completed including halite, schoenite, leonite, kainite and carnallite. Recovered salts have been sampled and are being dried at low temperatures for analysis and characterisation.

The final brine has been retained for further salt production trials and magnesium product evaluations. Trigg said interpretation of the trial results will begin once brine and salt analyses have been received.

KTMS processing routes

Trigg has been investigating alternative processing routes to improve the reliability of mixed potassium salt (KTMS) production during mining.

Preliminary testwork for one of the routes returned encouraging results from controlled salt production through the recovery of water from brine using established water recovery technology.

Salt characterisation from this work will be conducted during the March quarter to assist in establishing control conditions required to undertake further trials.

Lake Yeo project

Trigg has also been planning for an initial air core drilling program at the Lake Yeo SOP project, 35km south of Lake Throssell.

A works program describing the proposed activities was submitted to the Native Title determination holders and planning for heritage clearance surveys commenced. A schedule of works for Lake Yeo exploration has been approved by the regulator.

A schedule for an auger drilling program at the Lake Rason project, 100km south of Lake Throssell, was also submitted and approved during the December quarter.

Cash and equivalents

At year end, Trigg held $3.1 million in cash and cash equivalents following payments for exploration and evaluation expenditure of $1.4 million during the period.

The company raised $1.6 million (before costs) from a renounceable rights issue to continue its drilling program, progress evaluation studies and for general working capital across its portfolio.

In January, Trigg finalised its listing on the OTC-QB market exchange, facilitating the cost-effective trading of its shares in the North American market.

The listing will allow regional investors to trade the company’s shares in a US time zone with minimal additional compliance costs to Trigg.