I wouldn't be so quick to say Mt Ida Gold is toast.As Nathan...

I wouldn't be so quick to say Mt Ida Gold is toast.

As Nathan notes in the video, if its a chalcopyrite it can be floated into a concentrate and that is what Mt Ida has from the Gold JORC. You wouldn't want to be trying to it if gold was super-cheap, but it isn't.


There may also be substantial areas without copper issues. While there was a small operation around 2010, many years before that there was a signfiicnt operation that produced over 290,000 ounces of gold via UG shaft based mines. Gold was being produced so the copper issue was being addressed successfully, or copper wasn't an issue for most of the material being mined. At current prices of A$3,600/t the mine produced $1b of gold so a lot of value was extracted.

What if 70%, 80%, 90% of the gold seams are fine and had low or no copper and some of high copper areas were left behind. Early mining would look to removed the good-gold and leave the bad-gold with high copper in the ground. Assuming a good job was done in the older mining efforts, almost all the good-gold accessible by shafts is mined. Around the existing shaft structures, there's a gold-copper mix gold that's been left behind. Any indications of nearby good gold would have been chased and mined. The project would also have a local reputation for shopping around gold-copper ore to process because without a doubt, some gold-copper harder to process ore would have been brought to the surface.

Monarch would have known this but either thought they missed areas or thought that with their "superior skills" that they could recover the gold from the gold-copper areas left in the ground. They found it harder than though and ended up abandoning the mine again but it was only a small investment and gold was much lower than current prices. That likely confirms that a massive gold-copper issue exists on any gold near any existing shafts. Local knowledge about the mine would relate to its copper issues.

If this speculative idea is what unfolded, it doesn't however tell you anything useful about all the gold in seams that would be accessed via new open pit workings. Those seams could be copper-gold but they could also be non-copper gold deposits, or deposit areas with copper that can be extracted. The drill material through these unmined areas would be the key and Delta has that information from assay's and drill core's. For this to be a plausible scenario, ore body grades would need to vary across the ore body - but that happens.

Also its putting an uncomfortably large weight on a single word, but in Delta's Gold JORC, only "some" samples had elevated copper grades.

From Wikipedia:



From Monarch Gold's Dec 2007 Quarterly (the one linked in Wikipedia):