By examining the domain patterns present on individual grains of grain-oriented 3% silicon-iron it is possible to deduce the state of magnetization of the grain if reasonable assumptions are made about the underlying domain structure. Also, the magnetization of the sample as a whole can be found using conventional methods. By comparing the two observations we can gain some information on the part played by individual grains in the overall magnetization of the sample. Some preliminary investigations indicate a non-uniformity of flux distribution, between grains containing different domain structures, which may have a considerable influence on the anomalous losses in transformer steel.