Trigg Mining Limited (ASX: TMG) has announced highly encouraging results from the initial hand-auger sampling program over Lake Throssell in WA.
The company reported that hand-auger brine samples returned high grades of up to 6,660 mg/L potassium (K) or 14.8 kg/m3 SOP equivalent, with an average grade of 5,296 mg/L potassium, or 11.8 kg/m3 SOP equivalent from 18 samples.
TMG said that planning is underway to target the basal sand aquifer of the palaeochannel in 2020 including geophysical surveys and exploration drilling.
Trigg said that this indication of the potential mineralisation has led the Company to apply for two new tenements to the north and the south of Lake Throssell along the interpreted underlying palaeochannel, securing the Lake Throssell system.
Lake Throssell SOP project
The Lake Throssell Sulphate of Potash (SOP) Project covers 323 km² of predominantly salt lake playa sediments and underlying palaeochannels.
The Project is located 200 km east of Laverton on the Great Central Road connecting Laverton to Alice Springs and lies within the Ngaanyatjarra Native Title determined lands and a Native Title Agreement for exploration is in place.
Trigg is in the unique position of having 100% ownership of this significant sulphate of potash salt lake system covering 752 km2 and 106 km of trend; as well as a major transport infrastructure adjacent to the Project and only 20 km from the Yamarna Gas Pipeline.
Hand-auger sampling program
In 2017, Trigg and the Ngaanyatjarra traditional owners had entered into an exploration access agreement and under this agreement a heritage survey has now been completed paving the way forward for on-ground exploration activities.
Reconnaissance sampling was completed immediately after the heritage survey, collecting the very first brine samples from the lake to determine the tenor of the brine throughout the surface aquitard.
A hand-auger was used to establish pits up to 2m in depth and free-flowing brine was encountered 30 – 70 cm below surface in all 16 pits.
The company said that 35 samples and duplicates were submitted for analysis.
High-grade SOP discovery
The company announced that the results of the 18 samples submitted for analysis averaged 5,296 mg/L potassium, or 11.8 kg/m3 SOP equivalent with the highest result being 6,660 mg/L potassium, or 14.8 kg/m3 SOP equivalent.
Trigg said that the samples exhibit favourable characteristics for solar evaporative concentration and lower waste salts with a low Na:K ratio of 15.5:1 and a high SO4 concentration.
It may be noted that this brine composition is comparable to peers who have produced high grade SOP samples indicating equivalent process techniques can be used.
Two new tenements applied
Trigg said that the This indication of the potential mineralisation has led the Company to apply for two new tenements to the north and the south of Lake Throssell along the interpreted underlying palaeochannel, securing the Lake Throssell system.
This takes the Project area to 752 km2 and it is all prospective for SOP mineralisation with a 106 km trend.
Trigg reported that it has also entered into an agreement to purchase an additional tenement covering the western portion of Lake Rason.
The Company said that it has agreed to pay purchase price of $20,000 (exclusive of GST) for exploration licence E38/3437 which will increase the Project area by 96.2 km2. to 511 km2 upon grant.
Trigg said that the purchase price will be settled by the issue of fully paid ordinary shares in the capital of Trigg, the deemed issue price of which will be based on the volume weighted average price for the 5 trading days immediately prior to the grant of the tenement. The tenement is not expected to be granted until Q3 FY20.
The company said that additional ground in the Lake Rason area has the potential to enhance the anticipated Mineral Resource estimate following completion of sampling and drilling programs with 10 km of direct lake trend to be added to the existing 42 km lake trend.
The company reported that the next phase of exploration at Lake Throssell will target the palaeochannel and the basal sand aquifers.
Trigg said that planning has commenced to enable an initial air core drilling program in 2020 to map and sample the underlying palaeochannel; as well as additional near-surface sampling, with an aim to establishing an initial JORC Mineral Resource.
Trigg Mining’s Managing Director, Keren Paterson said: “The Lake Throssell Sulphate of Potash Project is shaping up to be a significant SOP project.
These high-grade results across the playa and the potential scale of the underlying palaeochannel makes this discovery one of the most important for Australia’s emerging SOP industry and our nation’s food security.”