Dave,
It should be brown or I did something wrong! My gum mix was about 4-1 of Burnt Umber to Indian Yellow; I figure if I want a warmtone then I want a WARMTONE
I'm loving the gum printing (and I have been doing a lot of straight gum printing--no gum over) and the endless opportunities and experimentation it offers.
In comparison to a straight Pd print, I find that my gum over prints (all 3 of them so far) have a lot more depth. One thing I have yet to try is doing a lamp black (very deep black pigment) over my pd and see what that does to the DMax.