I'm in search of a dark blue underglaze with good brushability. I want it to behave like ink painting- to be able to dilute to get value & maintain good brushability that is visible when painting on bone dry.
I've tried 2 different shades of Amaco's LUG series, but don't like the consistency, or visibility. I've also tried cobalt oxide with gerstley borate & frit, which brushes better and depth is more visible.
Wondering if anyone has experience with other commercial underglazes or recipes to share?