Rosie Huntington-Whiteley was spotted leaving a pal's house in Hollywood on Thursday afternoon, and the Transformers hottie covered up her flawless figure with a long skirt and top, but she did show off a decent-sized ring on her left hand.

So what's the deal with the sparkler? Rosie shot down engagement rumors earlier this year, and while we can't say we've seen this particular piece of bling on her ring finger before, she is a big fan of jewelry, so it appears as though this is just another piece in her collection!