I would agree with Jock Scot, JSFMACLJR and others above. In the British military I have seen buttons of every shape/size/colour/metal and all with their own pedigree. Don't forget that standardisation is a relatively modern phenomenom and garments and their accroutements where subject to a greater amount of personal taste in the past.
"O, why the deuce should I repine, and be an ill foreboder?
I'm twenty-three, and five feet nine, I'll go and be a sodger!
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