The vitreous paints I use are made by the L. Reusche company, clove oil
is one medium of several you can use with the pigment. The pigments that
I use mature at 1250 F. They can be purchased at local stained glass
suppliers or you can contact Ed Hoy's Int. that sells to educational
institutions. I have seen Ed Hoy's at our NAEA conventions as a vendor.
There is also an excellent text entitled, "The Art of Painting on Glass"
by Albinus Elskus which gives excellent illustrations and directions
with tools and techniques.