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It is argued that a high-temperature coated conductor, despite being very thin, is described by the same loss theory used for a typical low-temperature superconductor, except that it has anisotropy. However, it is also argued that in both cases for a more complete understanding of the general loss problem the existence of a surface charge must be added to the standard theory. The hysteresis and coupling current loss for a striated coated conductor in a strong perpendicular ac magnetic field (but without net transport current) is computed using the new theory. The total loss is then obtained by adding a term due to eddy current loss in the substrate. The coupling current loss is divided into a transverse and a longitudinal part, where the latter is neglected. The result is compared with measurements published by other authors.

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The temperature dependence of the crystalline anisotropy constants of iron, cobalt, and nickel is discussed. It is shown that Zener's result for iron (i.e., the first anisotropy constant varies as the tenth power of the magnetization) also may be derived from molecular field theory. In cobalt a satisfactory agreement with experiment is obtained by using Zener's results together with the postulate that the intrinsic anisotropy varies with thermal expansion in the manner recently calculated by the author. For nickel also the temperature dependence of K1 seems to require, in addition to the tenth power of the magnetization, a multiplicative factor that is linear in the temperature. No explanation has been found for this latter term.