Seller claims it's an O colored diamond.

[Gypsy]

http://www.ebay.com/itm/14K-Vintage-Art-Deco-Diamond-Ring-/370494273686?pt=LH_DefaultDomain_0&hash=item56432df896 Fascinating.

 

[LJL]

Eek! Maybe O means "Orange-Brown"

 

[luckky]

Either seller claims so far off from the true or may be not a good picture, if email seller and asking for the better picture might be really see it clear.

 

[asscherisme]

I think it is an "O" as in "Oh nO its nOt"!

 

[Gypsy]

Eek! Maybe O means "Orange-Brown"

I was thinking Cognac myself!

 

[GreenBling]

looks like a brown diamond to me