Paris Hilton Calls Off Engagement; what will happen to the ring?

Paris Hilton has called off her five-month engagement: [from WashPost, reg. req'd]

Paris Hilton has ended her five-month engagement to a Greek shipping heir. The celebutante-turned-model broke off the wedding plans with Paris Latsis...

"I'm sad to announce that I've called off my engagement. Over the last couple months I've realized that this is the right decision for me. We remain best of friends, and I'll always love him. I hope people will respect my privacy during this emotional time," Hilton told the magazine.

... Hilton, 24 and Latsis, 22, became engaged in the spring.

... Latsis gave the 24-year-old hotel heiress a 24 carat, $5 million diamond engagement ring. It was not immediately clear what would happen to the ring.

What's the usual practice for dealing with engagement rings when the engagement dissolves? Does the woman return the diamond?

What happened to that biggie that J.Lo received from Ben? I assume that the law of property and the common practice of returning the ring diverge on this question, but I don't know. Good question for my nephew to study in his prop/law course.

Special digression for regular EclEco readers:
I wonder if Paris Hilton has learned anything about string theory yet.