The earliest known and dateable Wileman & Co china patterns were all registered under the British Diamond mark system. Pieces decorated with the first four patterns are marked only with their diamond registration marks and no other identifying marks. Pieces with the fifth registered pattern have both a registered mark and the first known W&Co logo.
Diamond Registration Marks are coded, so a reference source which explains the coding system is needed to identify a pattern registered by Wileman & Co. The first five registered patterns and their diamond marks follow.