[Tarique Beg]

Hi Karin

I love using Prussian Blue but I read somewhere that it was extremely fugitive. The same with Van Dyke brown which I also like (it's not in your recommended palette).

I know the Windsor and Newton brands (the professional artist grade) are marked with a level of permanence. What is your long term experience with Prussian Blue?

I understand you study the old masters. So, I'd like to know what their opinion was of Prussian Blue?

I think Windsor and Newton also have two Alirizon Crimsons. One of them which, I'm told, has an almost imperceptible shade of difference from true Alirizon Crimson, is the permanent one, while true Alirizon Crimson is supposed to be notoriously fugitive. I'd also appreciated it if you have information on Vandyke brown.

The information I have of impermanence is from reading here and there and talking to art store owners. I'm sure you'd have better sources of information with your study of the old masters and their techniques.

Thanks,
Tarique