A very common  button worn by commissioned officers of the Royal Navy below flag rank 1902-1952 but only a few non maritime collectors are aware of the sheer number of different marks on the reverse. 

1/ .Gilt		2/ Gilt		3/ Gilt		4/ Gilt .

5/Gilt  .		6/ Gilt		7/Gilt		8Gilt /.

9/Gilt  .		10/ Gilt		11/ Gilt		12/Gilt .

13/Gilt  .		14/ Gilt		15/Gilt Gilt		16/Gilt .

17/  Gilt .		18/  Gilt		19/ Gilt		20/ Gilt .

21/ Gilt  .		22/  Gilt		23/  Gilt		24/ Gilt .

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