I think I stumbled upon Linux Mint on DistroWatch, upon this screnshot:
Somehow I wanted to see that wallpaper on my desk. Finally I found the image and put it up my desk:
It didn't take long to where I wanted a version without the mint logo on it. The logo is nice but I don't like to look at logos all day long. So I contacted the wallpaper's author Zwopper who sent me a no-logo version in both green and blue in no time also allowed me to share it with you under a CC-BY-SA-3.0 license here. As far as I understand they have not been published like that elsewhere before. Here they are.
Click the thumbnails for PNG downloads with 2560x1600 pixels size.