I am working on printing a personal large project for exhibit.
I have pretty well figured out the whole magilla, except for one challenging problem.
How do I get permanent shadow areas.

I am using a two dev solorazation wet print process and tri toning the prints .
Bleach / Sepia for the highlights, Gold which produces a nice peach tone in the upper midtones, and then presently iron blue for the shadows which give me a cold complimentary look to the shadows against the warm high tones.

My problem is the Iron Blue is not permanent and will fade over time, though the silver will still be there , I would like the blue to hold..

Are there any chem geeks here that would have a suggestion on how to mix a toner that will stick?
I have put a couple of attachments on how I like the look.
The sunflower has more bleach sepia gold.
The wheel has more iron blue.

I like both looks and want all the prints to be within these paramaters.
any help would be appreciated