Indoreksa represent Barium Sulphate products from Sachtleben, Germany.

Barium Sulphate are generally being used as filler / extender to reduce the use of pigment in order to reduce cost of paint.

There are 2 types of Barium Sulphate we can offer : natural and synthetic type:

Natural Barium Sulphate

Natural Barium Sulphate in general is not as clean as the synthetic type but it is low in cost. And due to the content of impurities, when it mix too much to the paint, not only it will reduces the strength color of the pigment but also will give certain degree of color change even to the extent of making it looks dirtier.
The good news is, Natural Barium Sulphate by Sachtleben is cleaner than what's generally available in the market. So the side effect fore - mentioned above is less.

Sythetic Barium Sulphate

It is much cleaner than the natural type. Hence it will not give too much effect on the color shift. Even better, for finer grades like Blanc Fixe Micro (particle size of 0.7 micron), it even enhances the color further since it improves the dispersability of the pigment.
Below picture show the whole range of Sachtleben Barium Sulphat, synthetic and natural, from coarse to fine.