Liam Hemsworth, Miley Cyrus engaged? Ring sparks speculation

(CBS News) Miley Cyrus sparked a flurry of engagement speculation over the weekend when she posted a photo of a sparkler on her left ring finger. The reported three-carat ring prompted many to wonder whether the 19-year-old star had gotten engaged to actor Liam Hemsworth, but insiders say the couple isn't walking down the aisle just yet.

The ring appeared as part of Cyrus' tweet about her new manicure:

Cyrus was spotted donning the same rock on Saturday when she and her "Hunger Games" star beau stepped out for Muhammad Ali's Celebrity Fight Night XIII event in Phoenix, Ariz.

Sources have since dished on the story, with one insider telling Us Weekly the sparkler is not an engagement ring.

The former "Hannah Montana" actress has yet to comment on the speculation, but she did refer to Hemsworth as simply her "boyfriend" in a later tweet.

Cyrus and Hemsworth, 22, have been dating on and off since meeting on the set of the 2009 movie "The Last Song."

Here's another photo of Cyrus' ring: