Alma Metals Limited (ASX: ALM) has confirmed copper-molybdenum sulphide mineralisation in multiple holes over a significant strike-length with further assay results from the current drilling programme at the Briggs Copper Project in Queensland.
Exploration at Briggs is being funded by Alma under an Earn-In Joint Venture agreement where Alma can earn up to a 70% interest from owner Canterbury Resources Limited via a staged earn-in.
The Project includes the Briggs Central copper deposit, where an Inferred Mineral Resource of 143Mt at 0.29% Cu has been defined. The current programme is testing Exploration Targets outlined at the adjoining Northern and Central Porphyry areas.
Drill hole 22BRD0014 was collared to test the northern part of the Northern Porphyry Exploration Target and is 180m to the north of 22BRD0013. 22BRD0014 intersected similar volcanic sediments and tuffs intruded by porphyritic granodiorites forming dykes and stocks.
The hole passed into a post-mineral intrusion at 528.6m down-hole depth and was terminated at 536.5m. All rock types other than post-mineral intrusions contain variable densities of mm- to cm- scale porphyry-style quartz veins and are variably mineralised with copper and iron sulphides as disseminations in the rock mass, and/or in the quartz-veins.
A broad interval (~140m) of well mineralized porphyritic intrusive, and the associated volcanic sediment contact zone, is observed in the lower portion of 22BRD0014.
This intrusive has no surface expression and its discovery opens significant exploration opportunities targeting higher grade zones of copper mineralisation, particularly in the contact zone along the north-eastern margin of the Briggs system.
Drill hole 23BRD0015 was collared 190m to the north of the Briggs Central Inferred Resource and is being drilled towards the SW to test for extensions of the inferred resource and to test a molybdenum anomaly in soil sampling which is offset from the copper anomaly. The hole was collared in porphyritic granodiorite but passed into mineralised volcanic sediments at a down-hole depth of approximately 40m.
The mineralised volcanic sediments contain several decimetre- to metre-scale granitic dykes and ubiquitous mm- to cm- scale porphyry style quartz-(feldspar-sulphide) veins containing visible chalcopyrite and lesser amounts of molybdenite. Assays reflect these observations with thick intersections containing both copper and molybdenum mineralisation. These are the best drill results for molybdenum to date at Briggs and warrant further evaluation to determine the economic significance of the molybdenum.
Assay results have been received for the top 332m of this hole only, with the final sample from 330m to 332m containing 0.69% Cu and 230ppm Mo. The hole was recently terminated at a depth of 608.3m, with assays for the remaining 276.3m of this hole expected in May.