Hello Shaz ,
What is your information source ? Where do you research autochrome ? Did you see the dye chemistry thread in APUG ? How will you press the glass ?
Please give us more details ,
I read someone saying crystal clear epoxy for glue the starch grains on to glass. But it tooks hours or day to set and your epoxy hardener might be very fresh otherwise you get yellow cast.
Not every epoxy is clear grade , you must call CIBA dealer to find crystal clear epoxy. Canada balsam is famous to disintegrate with moisture. But epoxy stay hundreds of years.
I will make a list of old threads in 20 minutes.
And I will pm you , take a look in to your message box.