Desliming of sample it’s a critical stage before doing LST separation, if your sample steel having slime it will affect in separation. Also LST density is important 2.82-2.85 and room temperature.

We are sitting with exactly the same problem with our project. We are about to embark another program of developing a standard. As we get results we will update.

I spoke with the lab manager of another operation and he told me that they do homemade standard by:

Doing HLS separation
Cleaning and drying both THM and Sand
Preparing 5, 10 and 80% THM samples

However, it’s still homemade and he would be glad to know if there are labs which can provide certified THM standards.
Does anybody know a lab for this kind of standard?

Desliming is key. This reflects the typical processing methodology in plant anyway. As far as developing a standard, I would recommend starting with an existing standard. Australian Coal has some very good ones for HLS work - procedures are AS 4156.1 (check if it is the current one at http://is.gd/1WACam).

Overall analysis is covered in the ACPS (Australian Coal Preparation Society) monographs (mainly Vol.1) which make reference to the standard and fill in some of the gaps as to the best methodology. See http://is.gd/2WMA8J for more information.

As you work for Rio Tinto you should be able to get access to any developments in the HLS area on ACARP also - some are directly applicable to mineral sands (I have found them quite useful for iron ore). http://is.gd/PnA5NH 

Thanks for the answers.

After having checked the above proposed solutions, I finally checked with the lab in charge of the standards for our Canadian open pit operation and they said that won’t be a problem to prepare standards for HMS samples used for HLS analyses. It won’t be too expensive and we will share the price with all our HMS operations. As soon as we get results, I will update this discussion to share our thoughts and conclusions about this project.