As in a 'dielectric' insulator- best choice is Mica-- Ashville NC and the old Diamond Mica Co. My GrandDad made a lot of molds for them in the pre-WW11 years.

Scrapple- my cardiologist would have a big chcukle out of that as a steady diet- like the Four Redneck food groups- Salt- Sugar- Bacon Grease and White Lightin'-- Wow