Sydney-based Lake Resources (ASX: LKE) has confirmed the large scale of its lithium brine-bearing basin within its Kachi lithium project in Argentina’s Catamarca province after encountering a highlight 308 milligrams per litre lithium with impurities at a low 4.3mg/L average ratio.
The company described its results as a definitive demonstration it had encountered lithium brines in “numerous horizons from surface to 400m in drill holes spaced 11km apart” at its wholly-owned project.
Lake Resources said brines with high conductivity and density, in the 1.18-1.22 grams per cubic metres grade range, had been intersected in thick sandy and gravelly aquifers.
The company is still waiting on results from depths greater than 200m which it said had promising conductivities.
Lake managing director Steve Promnitz highlighted Lake Resources’ drilling team had intersected a number of brine aquifers during its concurrent diamond and rotary drilling campaign.
“The significant scale of the Kachi basin is evident,” he said.
“We believe that there is a covered salt lake with an estimated area over 25km by 15km, hosting a very large brine body in sandy sediments with good permeability and low impurities.
“The higher lithium values with a low milligram-per-litre ratio in hole-003 area (were a) positive discovery and indicate good potential for future positive results.”
Mr Promnitz said three drill-rigs were on-site as part of an expanded drilling program designed to accelerate exploration efforts so the company could produce a resource statement for the basin prospect.
The drill team has been undertaking resource exploration drilling using a diamond-drill rig to collect drill cores for a porosity assessment and brine samples for the company’s resource estimation.
Production-well testing with rotary drill rigs is also being used to collect extra data for resource estimation efforts and to construct wells for test-pumping.
Lake said a US laboratory would analyse samples collected for porosity, with the Sydney company then to join up the results with systematic brine analyses from the drilling samples to produce a JORC-compliant resource estimate.
Pump testing has been planned for the near future as the rotary rig completed its replication of the diamond drilling in larger diameter holes, allowing for test production wells installation.
The pumps will then be able to push lithium brine into trial evaporation ponds and test extraction methods.
Drillers are targeting deeper horizons to locate higher grades and potentially extend the size of the brine mineralisation.
Lake Resources securities were unchanged at A$0.12 by late afternoon after achieving a A$0.14 intraday high earlier in the day.