Enamel in lump form is the least likely to break down over time and is preserved in it's purest state. This is truely a rare find. Forsythia when fired over copper makes a beautiful golden color.
Thompson Enamel for Copper, Silver, Gold, Iron and Steel. Should be fired at 1450 to 1550 degrees F. All Enamel is pre-1990, and lead bearing.
 "108 Forsythia (tr) Sold Out! THE RAREST LEADED BEARING ENAMEL!")