There are three die varieties for this coin consisting of three obverse dies paired with two reverse dies. 
Historical 12
St. Aubin's Castle
From "Historical and Topographical Description of the Channel Islands "
by Robert Mudie, 1840


1844
Penny
Obverse
Reverse


The spacing is measured between the fours.


Obverse Dies:  The Date



Narrow date


Wide date


Reverse Dies:  1/13

Normal bar

Long bar