Yellowstar Bentonite produces a calcium bentonite that can be easily activated giving you a sodic bentonite. Most of its uses are directly as a calcium bentonite though.

The benefits are described in terms of the following:

  • Supply
  • Sales Quantities
  • Chemical Composition
  • Shrink-Swell


The company has an above ground stockpile of more than 15,000 tons ready for dispatch. There is a further unmined orebody that has in excess of 10 million tons. Supply can be guaranteed! A time-consistency analysis has been conducted over a 3-year period and the variation in product deviated very little.

Sales Quantities

We are the only company in South Africa that will be able to supply you with Run of Mine (ROM) as well as milled and packed bentonite.

We can and do supply in:

  • 25kg bags (not palleted)
  • 1 ton bulk bags
  • 32 ton tipper loads


Yellowstar Bentonite has had its products tested and researched. It has been pelletised with coal, iron ore and chrome. It has shown to provide an excellent green strength. Several university level thesis have been written on pelletising projects where our product has been utilised.

Superior Product        

The calcium bentonite, such as produced by Yellowstar Bentonite, has been reported to be a superior bentonite to use than when using a sodium bentonite. This is widely described in literature generated by ferrochrome producers in South Africa.

Extract from thesis, Kleynhans, 2011

Chemical Composition

We have a well described chemistry that compares well with other bentonite deposits around the world.

Yellowstar Bentonite can be activated with various products. Common activators are:

  • NaCO3 – the most widely used activator. This yields an excellent swelling index. CEC rises linearly on activation.
  • NaOH – provides the highest swelling index but creates a corrosive hazard. Rarely advised.
  • Carboxymethyl Cellulose (CMC) is an excellent activator with slow deterioration.
  • Fly-ash – yields a highly plastic layer that does not crack easily when dried.

Fluxing Properties      

Extract from thesis, Kleynhans, 2011