Here's how you can install the Mylo Xylo round icon theme in Linux Mint 16.
1. Open a terminal window.
2. Type in the following commands then hit Enter after each.
sudo add-apt-repository ppa:noobslab/icons
sudo apt-get update
sudo apt-get install mylo-xylo-icons
Mylo-Xylo icons are round colorful icons designed for Gnome desktop and based on All-black icon set. It is under development and should not expect it as complete icon set but creator mentioned that version 1.0 will be complete set.More at Noobs Lab
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