What Raimey observed. Belgian bench test controller's (inspector's) personal marks used 1853-1877 were a smooth crown over the letter. After 1877, the inspector's mark was a star over a capital letter.
Some marks are however spangled, and it is likely inspectors used what they had.

I agree original or very long ago restored. It is impossible to reproduce the aged appearance of the Twist barrels by recoloring.

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