wonder what production is now?, page-13

No I do not work for MSC I do have a small holding of their shares

Some use "GE brightness" measure which does give a reading of over "95 GE"

Skardon are using the "ISO brightness" measure which is over "ISO 90"

A quick search on google I came up with tis site indicating price difference between Titanium Dioxide (Which MSC give a price @ AU$3200 a tonne and Calcined Kaolin)

From Click
The top contenders
Most of the interest in TiO2 extenders has focused on fine-ground calcium carbonate and calcined kaolin clays because of their low price--as much as 60-90% lower than TiO2