This work follows the study of the ecclesiastical geology of almost all Anglo-Saxon religious sites throughout England. There, it proved possible to both understand and distinguish clearly obvious patterns in the use of stonework, to determine the use and value of specific rock types, and to illustrate diagnostic features which could be used to identify building of that period. Subsequent studies of ecclesiastical sites, in Scotland and the Scottish Islands, the Isle of Man and Ireland expanded the value of the English studies by revealing closely analogous examples of the same indicative features. Beyond the domain of the Anglo-Saxons but of the same age, they were shown to follow a fashion; to this fashion the name ‘Patterned’ was applied.