This is a building that I have been working on to build my studio/school. I hope I can move soon...
Gum printing is a method where you use gum arabic, dichromate, and water color pigment to put a layer of color to a print. You can do as many layers as you want, which is necessary if you are doing gum alone.
You can do this method on top of other printing methods like Pt/Pd or even silver prints. You can see Edward Steichen's earlier work which he used this method a lot. They are beautiful prints.