Tiffany 925 Sterling Silver Necklace NOT Authentic

Beautiful 925 sterling silver necklace stamped “Please Return To Tiffany” on one side of the heart pendant. No blue box or blue bag, so I believe it’s not authentic. It’s probably been in my jewelry box for around 40 years. It’s very pretty and well made, definitely looks like the real deal but the toggle is plain and no ingraving on the back of heart. Definitely a quality 925 sterling silver necklace where ever it came from ☺️. About 15 1/2” in length. Heavy link and would be fun to wear!