I have a Greek Tetradracm, of the Old-Style Athenian/Owl type (rev is square incused). Its the right size for the type, and my scale says its 16 gms. The scale doesn't go into decimals so I think it might be a little heavier. I have some doubts about the authenticity, but I've never handled any of that type that was authentic. Anyway, I've been searching the web for a picture of the side of the coin. It seems like the metal on the side is flowing from a volcanoe. If someone can take a side view of a coin, I can compare it to this one. I'll try to take some pics of the coin later.... Thanks! Tom