Help with Tiffany & Co. (?) whistle

[pinckfur]

I came into posession of this whistle 15 years ago
but i dont know how old it is for sure. It is stamped...

STERLING
Tiffany & Co.
R (with a box around it)
+B (with a box around)
Co (with a box)

I've never seen these markings before so any information would be much appreciated- Thank you


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[dragonflywink]

Maker is R. Blackinton & Co., retailed by Tiffany.

http://www.925-1000.com/american-mfg2.html

Cheryl ;o)
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