A front end element, such as a shadow mask, for a color cathode ray tube is made from an alloy including iron and nickel as its principal components; and a black oxide layer is formed integrally on the alloy base. The black oxide layer consists essentially of a spinel-type oxide with the formula Ni.sub.x Fe.sub.(3-x) O.sub.4, where x is a positive number less than 3. A front end element constructed in this way produces a higher quality picture because of reduced thermal expansion.