Mystery piece of white metal????????????????

[mr d]

hi everyone this is my first post on this site

i have found a piece of, (im calling it white metal for now) and are having real trouble iding it.

it has 4 stamps, the first being a sidewards b. the ony other one i can make out it the letter g at the end. and the last but one looks like a tower or something

any help would be appreciated

thanks



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