Terrain Minerals Ltd (ASX:TMX, OTC:TMXAF, FRA:T4Y) has moved the Lightning Gold Project closer to a maiden mineral resource estimate after completing a 4-hole diamond drilling program designed to provide the final technical inputs for the July 2026 calculation.
The program at the 100%-owned project within the Smokebush tenure in Western Australia’s Murchison region totalled 671 metres, made up of 340 metres of RC pre-collars and 331 metres of diamond tails.
While the campaign was not aimed at making a new discovery, it was designed to de-risk the upcoming resource by collecting the density and oriented structural data needed for modelling, while also testing continuity within the Lightning and Monza structures.
That work appears to have achieved its purpose, with Terrain saying the drilling has now substantially reduced geological uncertainty ahead of the maiden mineral resource estimate.
Assays from the diamond core also backed up the company’s existing geological model and prior RC drilling, with the standout result coming from hole SBDD002, which returned 3.4 metres at 4.96g/t gold from 213.6 metres, including 1 metre at 10.93g/t from 214.25 metres.
Mineralised drill hole intercepts >0.5 g/t gold. All depths and widths are downhole. Intercepts calculated using a 0.5 g/t gold lower cut-off and a maximum of 2 metres internal dilution.
Other intercepts reported from the program included 2 metres at 1.14g/t gold from 112 metres in SBDD001, 1 metre at 0.65g/t from 127 metres, 2 metres at 2.18g/t from 176 metres in SBDD002, 1 metre at 0.79g/t from 214.25 metres in SBDD003, 0.6 metres at 0.65g/t from 101.3 metres, 0.3 metres at 4.62g/t from 127 metres, and a series of narrower hits in SBDD004 including 2 metres at 1.8g/t from 49 metres.
Importantly, Terrain said the diamond holes confirmed continuity of mineralisation along strike and at depth, while also supporting the interpreted plunge of higher-grade shoots within the Lightning structure. The drilling also extended across both Lightning and Monza, helping reinforce the broader geological picture.
The total drilling database now stands at 97 RC holes and 4 diamond holes for about 16,000 metres, giving the company what it considers a sufficiently dense dataset to support initial resource definition.
“Completion of this program marks a key milestone as we move toward our maiden resource at Lightning,” executive director Justin Virgin said.
“With the final dataset now in hand, we are focused on delivering a robust initial resource in July, which we see as the foundation for ongoing growth across the broader Smokebush system.”
Focus shifts to July resource and growth drilling
With drilling complete, Terrain’s next step is to fold the diamond core assays, density measurements and structural data into the geological and resource models through April and May, before moving into independent resource estimation work in May and June.
The maiden mineral resource estimate, covering both Lightning and Monza, remains targeted for July 2026 and is set to mark the project’s first formal gold inventory.
Beyond that milestone, the company plans to start preliminary metallurgical work to assess suitability for conventional processing, alongside induced polarisation work over the western part of the tenement to look for repeat gold-bearing structures.
Terrain also flagged further drilling after the maiden resource, with mineralisation still open along strike and at depth, leaving scope to grow the resource footprint beyond the initial estimate.