Tuesday, July 3, 2018

Altar - It's all about that As

Altar project, has a problem...

Come on babe, I'm about to put it down
And all that As
Go ahead and lock the door, you're about to work it out
And all that As
Won't you lead me to your whoopee spot?
Oh it don't make no sense all of that As you got
'Cause I done called it too that you see booty flu
With all that As

Oh baby all that As

Whip your hair in those stiletto heels
And all that As
I'm about to dress you up in hundred dollar bills
And all that As
Driving me crazy baby don't you pump the brakes
You better call the cops, I'm about to steal the cakes
On all the evidence they got my fingerprints
On all that As

Oh baby all that As

Or visually,
Source: 2013 technical report - Stillwater mining
This shows that there is an ~inverse ratio between As and Cu. So, high-As in the low grade (<0.4% Cu) and lowish As in the high-grade (.0.5%) core. However, we still see that concentrates produced by Altar will probably contain at least 1% As.

Why is this a problem? Penalties - here is a nice article for a few years back from International Mining (link). Highlights:

  • China Imposes a limit of 0.5% As on imported base metal concentrates
  • Few smelters will treat >1% As and will charge a penalty to do so (link)

It's all about that As


  1. As in concentrate is a problem but not a fatal flaw. As noted, there are smelters that take high As concentrate and charge a penalty. I think it's an extra $2.50 per tonne for every 0.1% above penalty threshold. So it would add to TC/RC's, which typically amount to about 10% to 15% of total costs.

    Traders will take high As con and blend it with clean con to get a mix that meets smelter requirements. But selling to a trader means taking your loss up front instead of waiting for the results from the smelter.

    Aranzazu is a project with high As.

  2. It could be for a marginal project (e.g. Altar Global resources, if there was no high-grade core), but more likely to be a reason used by a company to take an internal decision not to develop it.

    At least it will be a question that Aldebaran will need to approach. However, it may have been something simple like a small met sampling being biased by a high-grade sample that skewed the data.

    1. The bigger and perhaps biggest risk on the project is location. Few companies want to take on the risk of operating in Argentina. But you're right...it will be an issue to resolve if they intend to develop the project. Because of the low grade it would have to be a high tonnage operation, producing high volumes of concentrate. It would be difficult to sell high volumes with high As because of the need to blend with cleaner stuff. None of the smelters that handle high As are in favourable geographical locations, so transport costs would also be much higher than normal. (Tsumeb is 800 km from Walvis Bay as an example.)

  3. All I can say is that my 'Booty' needs has been filled for the foreseeable future. Thnxs for that AG.

    Yep. Too much AS is sometimes a baaaad thingy.