A tip credited to Valeri Timofeev .
“thick metal = thin enamel, thin metal = thick enamel” This means if you are enameling say cloisonne, you can get pretty thick enamels on the metal plate of your choice, as long as you counter the same thickness. I have enameled to a mm in thickness on 20 ga metal= thin metal. But if you have 16 ga metal and want to enamel on it, you can do so with one layer of enamel and no counter.
enamels are approximately 1mm in depth.
And here on the left is thick metals of 16 ga with one coat of flux and one color of red enamel.