Sam, RT Mart, training ceramic color matching class. RT Mart Sam Training Ceramic Coloring Class provides free video tutorials on ceramic tile color matching skills, and even ps graphic tutorials on ceramic tile color matching skills, after-class exercises and works evaluation. It is the best learning institution for ceramic tile color matching. Ceramic tile, also called ceramic tile, is a kind of acid and alkali-resistant porcelain or stone, which is made of refractory metal oxide and semi-metal oxide through grinding, mixing, pressing, glazing and sintering.