Things that make you go, hmmm. Chris Martin has only been officially single for a few days, but is he on the verge of re-coupling with his girlfriend?

The Coldplay frontman has been dating English actress Annabelle Wallis since March and she recently posted a picture to Instagram to clearly shows her wearing what appears to be a diamond ring on THAT finger.

Annabelle was apparently on her way to a friend's wedding before taking the picture.

"Perfect dress for a wedding. Thank you .@maleneoddershedebach #terribleatselfies @jimmychoo," she wrote.

She made not mention of the bauble on her left hand.

Although Chris and Gwyneth Paltrow split -- or "consciously uncoupled" -- in 2014, their divorce seemed to move at a snail's pace, and only finally became official on July 14. In fact, as neither seemed to be in any hurry to push the divorce forward, many wondered if they were going to get back together.

They have both praised either in the press and are often seen together with their children.

Of the split, Gwyneth told Red magazine in April, "... It's also almost about having to press the 'override' button whenever you feel angry or jealous or whatever, broken-hearted," she explains. "You have to press the button -- I'm going back to the baseline of I love this person, he's the father of my children, he's a wonderful man. I'm just going to put my s--- aside for right now."

She continued: "It really has not been easy for me at times, I'm sure it's not been easy for him. But when we said we're going to put the children first, we meant [it]. If you want to put your children first then why are you slagging your husband off in front of them?

"So we really tried [and] that meant I'm gonna check my s--- at the door, and I'm going to focus on all the reasons that I love you, that you're like my brother and my family forever and we'll deal with that stuff another time. It's not always easy, but it's just the way we wanted to try to do it. I have to say it wasn't the outcome we were hoping for, but it was our outcome and we've really done the best that we can."