The Mercers’ Maiden is the symbol and the coat of arms of the Company.
She first appears on a seal in 1425. Her precise origins are unknown, and there is no written evidence as to why she was chosen as the Company’s emblem.
She always adorns the exterior walls of buildings on sites that belongs to the company.
The one here is the earliest surviving Maiden property mark dating from 1669. It was reinstated on this site during redevelopment in 2004.
You can find the map of all of them HERE and have some fun finding then.