Nagambie Resources builds mineable antimony-gold intersections at namesake project
Resource Base has positioned itself to play a key role in unlocking the “globally significant” emerging ionic clay rare earths precinct in the southern Murray Basin.
Nagambie Resources (ASX: NAG) has boosted its antimony-gold mineable intersections to 18 after receiving more assays from drilling the C1 vein system of its Nagambie historical mine in Victoria.
Nagambie was a heap leach gold mine that operated in the 1990s and retains a granted mining licence.
The company has been actively drilling the ground to build new mineable reserves and announced the discovery of the C1 antimony-gold vein system in November last year.
Another vein system C2 was discovered in January.
Nagambie has now received assays from drilling the C1 vein system, which have revealed a further six mineable cut-off grade intersections (MCOG).
Highlight MCOG intersections comprise 2.7m of estimated horizontal thickness (EHT) at 26.8 grams per tonne gold equivalent; 2.4m EHT at 8.3g/t gold equivalent; and 1.3m EHT at 12.6g/t gold equivalent.
Within the new assays peak grades were 48.3% antimony, 19.9g/t gold, and 112.2g/t gold equivalent.
The 18 mineable intersections were identified across C1 and C2 vein systems and had an average grade of 15.6g/t gold equivalent (5.5% antimony plus 5.1g/t gold).
Mineable material
Nagambie executive chair Mike Trumbull said it was important to note the grades for all mineable intersections allowed for waste dilution.
“The constraints of mining equipment mean that the minimum horizontal width that can be effectively stopped (mined) is 1.2m.”
“Hence, any mineralised intersections narrower than that are bulked out with waste rock up to 1.2m, reducing the average grade accordingly.”
He added this means the average grade of the vein or veins within the minimum 1.2m could be “considerably higher”.
“This method of reporting gives a much more meaningful indication of the actual grade and tonnage that could be mined, as opposed to simply reporting the down hole lengths of mineralised samples and the assays for those samples.”
Nagambie veins and mine plans
The mineralised veins discovered at Nagambie to-date are sub-vertical – 45 degrees to 90 degrees vertical.
Mr Trumbull said the veins have good continuity both horizontally and vertically, and could be amenable to mechanised, productive mining methods similar to TSX-listed Mandalay Resources’ nearby Costerfield mine.
“Conceptual mine planning for a Nagambie underground mine already indicates that mining only the C1 and C2 vein systems sufficient stopes could be developed to effectively schedule stoping operations and optimise the antimony and gold grades delivered to a flotation treatment plant.”
Mr Trumbull said drilling was ongoing and targeting of further C-vein antimony-gold systems.