Kalgoorlie Gold Mining has opened a fresh front in its search for hidden riches in Western Australia’s Eastern Goldfields, defining multiple gold anomalies from first-pass aircore drilling at its regional-scale Laverton Tectonic Zone (LTZ) Flexure target.
The program focused on KalGold’s Pinjin gold project, 140km north-east of Kalgoorlie-Boulder in the southern part of the LTZ. The LTZ is a major crustal-scale structure known to have acted as a pathway for mineralising fluids responsible for numerous significant gold deposits across the Eastern Goldfields.
KalGold drilled 225 aircore holes for 7212m on a line spacing of 320 m to 400m apart, with holes averaging just 32m deep. The first-pass program targeted gold beneath transported cover, where the company believes bends and faults along the LTZ may have concentrated mineralising fluids into new deposits.
Individual assays were modest, as expected from early-stage regolith drilling, with results reported using a 0.1 grams per tonne (g/t) lower cut-off. They included 1m at 0.378g/t gold from 41m, 4m at 0.167g/t from 36m and 1m at 0.196g/t from 40m.
The broader result was more significant. KalGold used a cumulative down-hole gold threshold of 20 parts per billion (ppb) to define several coherent zones of anomalism, including a trend extending for up to 2km of strike through the northern half of the drill grid. The threshold is roughly ten times typical background in Yilgarn laterite and ferricrete.
At Pinjin, the regolith — weathered rock and transported surface material above fresh bedrock — can preserve geochemical clues to concealed mineralisation. These gold traces line up with magnetic rocks, possible faults, and other geological features KalGold identified from an aeromagnetic survey prior to drilling.
The company says the way the gold traces line up with geological and magnetic features supports its exploration model and gives it a ranked set of targets for testing in fresh rock below the weathered zone.
For KalGold, the significance is that a previously untested structural flexure has now been converted into a coherent pipeline of follow-up targets.
Kalgoorlie Gold Mining managing director and chief executive officer Matt Painter said: “The first-pass aircore program at the LTZ Flexure has successfully opened up a previously untested area of the Pinjin Gold Project, identifying multiple coherent gold anomalies along the region’s principal gold-mineralising structure.”
With a swag of new targets in hand, KalGold is planning its next moves. Deeper reverse circulation (RC) drilling will test the regolith targets for primary gold at depth, with the larger rig able to penetrate fresh rock and determine whether the shallow anomalies connect to a more substantial system.
The RC campaign is expected to run alongside first-pass aircore drilling of the Rebecca Sequence, a concealed geological structure immediately north of the current grid. Earlier limited drilling returned low-level gold anomalism with a possible antimony association, distinct from the stronger arsenic association in the Pinjin Sequence. Work is scheduled for mid-October, although heavy late-September rainfall has closed roads across the Eastern Goldfields and may affect the final start date.
The broader structure is no stranger to gold mineralisation and already hosts Ramelius Resources’ 1.4-million-ounce Rebecca gold project, 16km south along strike.
The company's LTZ Flexure sits 3.5km south-east of KalGold’s Kirgella Gift and Providence deposits, which contain an inferred resource of 2.34 million tonnes at 1.0g/t gold for 76,400 ounces. Pinjin also includes the exciting Lighthorse discovery, which delivered some serious gold hits in early 2025, led by a standout 3m at 9.01g/t from 145m, including 2m at 12.69g/t, within a broader 22m zone grading 1.58g/t gold alongside other promising targets such as Wessex, T12, T15 and Providence South.
Follow-up drilling at Lighthorse has confirmed primary gold beneath a shallow supergene blanket, with the anomalous footprint extending for around 1.45km. Kirgella Gift mineralisation, meanwhile, has been traced to roughly 300m vertically.
The LTZ hosts a conga line of major gold deposits, including Sunrise Dam, Wallaby and Granny Smith, along a geological structure associated with more than 30 million ounces of historical production, reserves and resources. Their scale may not guarantee a similar outcome at Pinjin; however, it does highlight the fertility of the regional gold system.
KalGold’s systematic approach of applying modern exploration techniques beneath the surface cover in a world-class gold belt appears to be paying dividends. The next phase of drilling will test whether the new signals are merely smoke, or the first visible trace of a larger concealed system.
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