Extremely Rare British Boer War / WW1 Period Entrenching Tool

An Extremely rare British issued / trials entrenching tool in well used condition, stamped on the neck with Mads Johan Buch Linnemann`s Patent of 1869.
Due to lack of information /reference on this pattern it is difficult to place an exact year of issue.
Ordnance mark to the wooden handle along with a couple of old worm exit holes.
Originally would have had a serrated edge to one side but now missing due to heavy wear, even in this semi-relic condition it is considered to be very rare.
A serrated edge example is on display at the Flanders Field Museum but uncertain if it is of British manufacture.

Code: 50226