Strickland Metals has intercepted promising shearing and alteration in four diamond holes completed at its Marwari gold play near Wiluna in Western Australia, with a fifth hole in progress at the company’s intriguing new focus ground.
It follows revelations 10 days ago that it had suddenly redirected all of its reverse-circulation (RC) and diamond drill rigs to Marwari, sending its share price on a tear. Marwari is a new, high-grade gold target within Strickland’s Horse Well prospect in the Yandal greenstone belt, about 85km north-east of Wiluna.
Just a week before the wild ASX share price ride started, the company said it had planned to start a two-hole, 440m diamond drillhole program to home in on Marwari, where reconnaissance air-core (AC) drilling in September produced a decent gold hit of 31m at a grade of 5.6 grams per tonne gold from 72m to bottom-of-hole, including 8m at an attention-grabbing 17.7g/t gold.
Management said it believed the intercept may be the harbinger of a new gold trend. The market then stood to attention when the company said the first of its two diamond holes, originally planned for a target depth of only 180m, would be extended for a further 111m to total depth of 291m.
Strickland then added that it was also assigning its RC rig to a program of aggressive pattern drilling on a 40m-by-40m grid through an initial 300m of strike south of the discovery hole and setting up three more pre-collars for the diamond drill rig.
There were no assays then to give any clue to the reason for the urgency being given to proposed additional drilling – and they are still pending. But the first diamond hole gave adequate visual indications that something interesting might be about to unfold.
Strickland Metals chief executive officer Andrew Bray said: “All four holes have intersected the target stratigraphy, albeit over greater widths than initially anticipated. Given the size of the units intersected down-dip from the high-grade discovery hole; the fact that the same unit has now been intersected 80m along strike; and the apparent accuracy of the magnetic inversion model, Strickland is of the view that these visual observations warrant reporting.”
As revealed 10 days ago, the first diamond hole, a step-back under the discovery hole, intersected strong alteration (hematite, carbonate, chlorite and in places, sericite), veining and sulphides from about 128m to 205m. Intercalated banded-iron formation (BIF) and intermediate volcaniclastics continue to 230m. The footwall intersection, ending at 270m, comprises conglomerate and finer grained metasediments, notably still with strong silica and carbonate alteration, shearing, and brecciation with pyrite.
The main alteration styles seen in drilling to date include silica-carbonate-pyrite flooding associated with the most intense (mylonitic) sheared zones and carbonate-pyrite-hematite associated with carbonate-chlorite veining. Drill core in all four holes are generally showing similar intense alteration, veining and shearing.
In the second hole, which was drilled under the first, the geology is similar to its predecessor, but occurs over a greater width from 180m to 270m. It also has stronger quartz carbonate veining, alteration and sulphide, with the most visually impressive parts in the broader intersection observed between 203.8 to 220.9m and from 239.9 to 259.6m.
Encouragingly, the geology, alteration and veining match up with the geology reported in the original AC discovery hole up-dip.
The third diamond hole targeted the centre of the modelled magnetic inversion and was drilled 80m to the south of the section line, which comprises the discovery AC and first two diamond holes. It also intersected the same style of alteration and veining from 182m to 261m and contained impressive, localised sections of intense veining and sulphide content observed between 187.5m to 199m and 246.7m to 251m.
It features a zone of about 50 per cent quartz carbonate pyrite breccia, with up to 20 per cent pyrite sulphides between 259.5m and 260.7m.
The fourth diamond hole was drilled 40m south from the discovery hole, targeting shallower mineralisation. It successfully intersected veining in the BIF and weathered near-surface rock, which correlates well with the oxide gold grades intersected in the discovery hole.
Drilling on in fresh BIF, intercalated with intermediate volcaniclastics from 120m to 141m, the hole exhibits variable veining, sulphides and alteration concentrated around veins and structures and a notable zone of intense shearing, with about 20 per cent quartz veining, 5 per cent pyrite and hematite-sericite-chlorite alteration from 137.2m to 141m. Structural measurements from the hole provide stratigraphic information, enabling the geometry of the main BIF body at its lower contact to be estimated as dipping 81 degrees to the east.
Strickland says in other work at its Konik discovery, first revealed early last month, its scout AC holes could not penetrate the fresh rock to test the targeted structure. But a 450m-long shallow gold trend – with results above 0.5g/t gold – has been outlined along a north-west-striking shear structure coinciding with magnetic highs.
Konik appears to be on a zone of structural dislocation between a major north-east/south-west fault and a dislocated set of north-west/south-east-trending tensional shears.
Strickland says it plans to revisit Konik in the new year when it will assign an RC drill rig to the task of deeper drilling and sorting out the geology.
The company says it expects assays from diamond drill core to be available for the first hole as early as the end of this month, for the second and fourth holes before mid-next month and for the third hole in early to mid-December.
Strickland seems to be generating targets almost faster than it can test them. Now it is waiting to see if the next stop is the stratosphere.
Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au
By Doug Bright
