I would like to ask those with experience about pigmentation of enamels ( the type intended for use on metal ).
I am interested in creating "inbetween" colors for color graduations.
My experiments have been as follows...
1. Finely mix two differently colored powdered (opaque) enamels >>> result - "spotty"
2. Finely mix, grind and sieve two powdered enamels >>> result - much better but still "spotty"
3. Finely mix, grind and fire ( typically 850 C | 1562 F ) two enamel powders, regrind, re-fire and repeat >>> result - best yet - hard to tell due to limitations in my method ( need to build a decent device for reducing larger flakes before grinding to a powder ).
4. Introduction of ceramic pigments from Thompson enamel supplies. I believe these are fritted and not pure oxides >>> result poor - pigment floats to the surface and is grainy. Not the desired result since I then go on to grind the surface smooth for a matt finish which is my preference - pigment is not taken into the body of the enamel its a superficial surface effect.
Any pointers to reference material or similar that will help me educate myself on the subject of how pigments are ( or are not ) fully absorbed into frits and glazes would be gratefully received.
At the moment I am working on the assumption that perhaps my temperature range ( traditional enamel temperatures up to 850 C | 1562 F ) are not capable of fully dissolving pigments into the glass - however I read somewhere that good pigments are insoluble in glass so I am probably off the mark here?