The porcelain knives from Porsgrunds Porselænsfabrik are made from a material that places them just below diamond on the Mohs scale of hardness. This means that the knife edge retains its sharpness much longer than knives made of steel. Porcelain knives will also never rust and do not alter the taste of food in the way steel knives can with some ingredients. In addition, the knives are lightweight and easy to clean.
For example, if you cut an apple in half, it will quickly turn brown due to a chemical reaction between the acid in the steel, the apple, and the surrounding air. Porcelain is a "dead" material and delays this browning process by approximately 3-4 times longer.