Hi folks, rather than wait for some copper experts to give us a...

Hi folks, rather than wait for some copper experts to give us a brief I spent the last hour or so becoming an instant on-line expert. The focus of my research was on interpreting and assessing copper grades.

I found a fair bit of research on copper and had a look at the copper grades of a large number of mines.

In short world copper grades are declining. One authority stated that the average grade of copper on planet earth currently stands at .79%. One source stated that the average grade in the likes of PNG is .46% (similar in the Philippines). In the US it is .51%. In Zaire it is as high as 4%.

Another source indicated Canada to average 0.3-0.5% and Northern Mexico to average 0.4 to 0.8%.

I had a look at a number of mines in Australia and elsewhere. There are mines in Australia with grades less than Marengo. The Xtrata Tampakan project o/s has an average grade of .51 and the Lomas Bayas open pit mine in Chile as low as .27%.

Having said all this the profitability of a mine, from my research, depends on a number of factors of which the grade of the copper is but one.

Factors include the price of copper, the cost of extracting the copper, the depth of the copper. Essentially it comes down to the cost of handling the copper. Improvements in processing technology have reduced these costs. I note Marengos announcement of higher grade deposits closer to the surface. The amount of measured resource also counts.

After a cold and windy afternoon indoors looking at research on copper, I have learnt two things. One, I wish I paid more attention and do more work in high school science and secondly, the Marengo grades of copper are okay, particularly when considered in light of the huge amount of it they have.

I will happily stand corrected by anyone who actually passed yr 8 science.