I purchased this green cocktail ring in an online auction in 2013. It was described by the auctioneer as citrine, Sterling, size 6.75. It is difficult for me to photograph, but it looks to me like it is marked 18KGF for gold filled. Please note that I am not an expert.

The stone is light green, faceted, square, and measures about 3/8." The metal on the top half has an intricate braid design. The band is smooth in the back. 

Shipping: I will ship wrapped in tissue paper and large cushion bubble wrap in a small sturdy box. Thanks for looking.

According to gia.edu.com: Along with topaz, citrine is a birthstone for November. It’s also recognized as the gem that commemorates the thirteenth anniversary.