Vintage Unbranded Clock Crank Key

Brass with dark wooden handle grandfather clock crank with some wear. It is not stamped in size but my best guess compared to ones I have is it is a 10 or an 8 or around that size. For sure smaller than a 12. Please see pictures for details. 

Please note that color may vary a small amount because of my lighting. If you have questions please ask and I would be happy to help! -Michelle