It is an Asscher cut (square emerald cut) loose diamond that was purchased for $5500. I have priced out similar in the stores and they still sell for over $5000. It is beautiful in person and I get many compliments on the stone from other jewelers when I have them clean it.
My husband proposed with this diamond ten years ago at sunset at the top of the empire state building in NYC. I am only selling it so I can upgrade to a larger diamond but more simple band set as my tastes have changed. I am still going to get an Asscher cut, though. It is so unique and different, everyone compliments me on it.