My apologies for not providing a photo of the marks, but they're so tiny I can't get them to show up in a photo. These candlesticks are marked with the words "Sterling Reinforced with Cement & Steel Rod" and the number 6511. Above that is a block letter R in a square with rounded corners and a block letter B in a square with rounded corners. These letters are about 1/16 of an inch high. Attached (I hope) is a photo of the candlesticks themselves. Can anyone identify the RB mark, please?

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