Miley Cyrus posted a pic on Instagram which shows her and Liam Hemsworth posing for an XMAS photo, and we noticed something interesting ... Check out Liam's left ring finger -- it looks suspiciously like a wedding band.  The pose blocks Miley's finger.

They got engaged earlier this year but made no announcement about a wedding date. 

And as long as we're talking, also take a look at another pic Miley posted, show her in a Santa's getup.  It looks like she might have 2 bands on her ring finger, one being her engagement ring.  

The other?  

(TMZ)