In glaze chemistry, theoretical materials are used to represent what a material would be if it was uncontaminated and perfectly crystallized
A material the way it would be if its crystal structure perfectly matches the unit-cell drawings you find in textbooks. In nature, materials are always contaminated to some degree. Calcium carbonate is never pure, feldspar never has an ideal 1:1:6 relationship between fluxes:alumina:silica, kaolin particles are never crystal-perfect, etc. Some materials are theoretical in physical properties but have no theoretical formula (e.g. ball clays) because they are a mix of many minerals and have a definition that can encompass a broad range of products. When learning ceramic chemistry students usually use theoretical materials (e.g. potash feldspar, kaolin). However when they begin working in the lab of a company they use the actual chemistry of real world materials.
Desktop Insight 1A - Compare Theoretical and Real-World Feldspars
While comparing a real-world and theoretical feldspar learn to enter, edit, save, normalize recipes and the materials dialog. Glaze chemistry concepts.
Ceramic materials are employed in the ceramic industry to make glazes, bodies, engobes and refractories. We study them at the mineral, chemical and physical levels.