Australia's deepest gold mine

[Anolphart]

Interesting article about Gwalia and how deep the mine goes.

I'm not sure whether to believe their comment of "For every tonne trucks cart to the surface there might be only seven grams of gold, the equivalent of about one teaspoon. ". I doubt that they would stay in business too long with those sorts of payloads.

https://www.abc.net.au/news/2019-04...deepest-gold-mine-and-getting-deeper/11004444

 

[user 4386]

Interesting article about Gwalia and how deep the mine goes.

I'm not sure whether to believe their comment of "For every tonne trucks cart to the surface there might be only seven grams of gold, the equivalent of about one teaspoon. ". I doubt that they would stay in business too long with those sorts of payloads.

https://www.abc.net.au/news/2019-04...deepest-gold-mine-and-getting-deeper/11004444

Seven grams per tonne is actually high-grade (although required for profitability in deep underground mines). That is around a quarter of an ounce, so $325 per tonne, And of course every truck contains many tonnes (eg 100 tonne = $32,500 per truck). Just give me a few truckloads of that gold!

 

[user 4386]

It was around 2 km deep last I heard (Bendigo once had one of similar depth I think, not quite that deep). It is the Hoover decline (President Hoover of the USA used to be the mine manager there, as at Big Bell and even at Creswick - he caused the Kalgoorlie race riots). I have been down to nearly 4 km in a South African gold mine (Western Deep Levels). It is hot down there, and the floor is as likely to slam you against the ceiling as vice-versa.

 

[Jaros]

Good reading -thanks.

 

[Anolphart]

Fair call, I didn't do the sums.

 

[Mackka]

Yeah My wife read that to me this morning and I thought the same thing as Anophart, to me it just didnt seem viable.
I thought I read on here someone claiming an ounce to every 10 tonne. That to me is profitable.
Nice maths Goldie.
Mackka

 

[cairnspom]

Yeah My wife read that to me this morning and I thought the same thing as Anophart, to me it just didnt seem viable.
I thought I read on here someone claiming an ounce to every 10 tonne. That to me is profitable.
Nice maths Goldie.
Mackka

But an ounce per 10 tons, is only 3.1 grams per ton!

 

[Mackka]

See thats why I am not good at maths.
Mackka :Y:

 

[cairnspom]

See thats why I am not good at maths.
Mackka :Y:

But I understand...It sounds more!

 

[user 4386]

Is my maths out? But I think you get the point. And 3.1 grams per tonne is a bit low underground (Stawell has been profitably operating on 4.2 g/t over decades at a kilometre deep). I once asked my students to calculate the total production of a particular goldfield (I used to make them do estimations like that so they had a grasp of economic realities). One gave a figure ten times the entire historical production of the world......

But think of Fosterville mining at similar depth to Stawell now - they mine it at $650 per ounce mining cost and produce 600,000 ounces per year (and will for years).

 

[MacRob]

Watching a news item on ABC last night about the Gwalia mine near Laverton WA. Amazing that they are working 1600m below surface and moving 1.2 million tonnes per year of hard rock to get to the good stuff. In 2009 the first 100,000 oz milestone gold pour was reached since the redevelopment of the mine.