Any Tiffany&Co experts out there?

[LadyHawk]

I just received a purchase I made on ebay-it was listed simply as a rare, hexagonal diamond ring. When I louped it, I discovered that it is a Tiffany & Co. piece with an engraved date of June 22, 1938. I thought it was a firerose cut since it was 6 sided, but all the info I can find on that cut says that it first came out in 1989. Does anyone know anything about vintage T&C pieces and can you help me determine the value? It is approx. .45cts, 18kt yellow gold and the diamond is set in IRID.

 

[Iceman]

Does it look like this ?

 

[LadyHawk]

It is six sided. Did they cut a six sided version of this diamond? I first thought it was a firerose cut, but I am not sure if they existed back in 1938-I was thinking that T&C had their own version of a six sided diamond.