At the end of the 1997 movie, "Titanic", what did Rose do with the necklace?

At the end of the 1997 film Titanic, Rose threw the necklace overboard into the sea.

The necklace is the Heart of the Ocean, a large blue diamond pendant originally owned by Cal Hockley, Rose's wealthy fiancé. Cal hides it in the coat he gives Rose during the ship's evacuation, unknowingly allowing her to keep it after she escapes the sinking Titanic and reaches New York under the name Rose Dawson.

Decades later, the elderly Rose recounts her story aboard the research vessel Keldysh, where Brock Lovett and his team are searching the wreck for the diamond. Rose has secretly retained the necklace all those years. After Lovett abandons the search, she goes alone to the stern of the Keldysh and drops the pendant into the ocean above the wreck. The act symbolizes her refusal to let the diamond—and the wealthy world Cal represented—control her life.

A common misconception is that Rose lost the necklace during the sinking or returned it to Cal. She did neither. The film shows that she deliberately kept it and then chose to release it. The closing dreamlike scene of young Rose reuniting with Jack is separate from the physical act of throwing away the necklace.