In The Fellowship of the Ring, Gandalf relates the following exchange between Sméagol and Déagol:
‘“Give us that, Déagol, my love,” said Sméagol, over his friend’s shoulder. ‘“Why?” said Déagol. ‘“Because it’s my birthday, my love, and I wants it,” said Sméagol. ‘“I don’t care,” said Déagol. “I have given you a present already, more than I could afford. I found this, and I’m going to keep it.”
This occurs shortly before Déagol is murdered for the One Ring.
What was that object? Could it have had any influence on Sméagol's decision?