Install Opal Blue & Blue + Smooth theme on Ubuntu/Linux Mint (GTK + Gnome Shell)

Install Opal Blue & Blue + Smooth theme on Ubuntu 12.04/12.10/11.10/Linux Mint 13/12 for GTK3 + Gnome Shell 3.4

Opal Black and Blue theme is actually Black Opal distro theme, This theme is really looks cool. Opal theme is available in Blue + Black and also available smooth version for Gnome Shell 3.4.
Here is Black Opal Distro for 64bit.
You can use these Tools to change theme and icons: Gnome Tweak Tool, Ubuntu Tweak

Download Black Opal Distro Wallpapers
Install Opal-ACYL Icons

Gtk Theme

This theme available for Ubuntu 11.10/12.04/12.10

To install Opal Blue+Black Gtk theme on Ubuntu/Linux Mint open Terminal (Press Ctrl+Alt+T) and copy the following commands in the Terminal:

Terminal Commands:
sudo add-apt-repository ppa:noobslab/themes
sudo apt-get update
sudo apt-get install opal-theme

Gnome Shell Theme

This theme support Gnome Shell 3.4 and available for Ubuntu 11.10/12.04/12.10

To install Opal Smooth Gnome Shell theme on Ubuntu/Linux Mint open Terminal (Press Ctrl+Alt+T) and copy the following commands in the Terminal:

Terminal Commands:
sudo add-apt-repository ppa:noobslab/themes
sudo apt-get update
sudo apt-get install opal-smooth-inset-3.4

That's it

Source: Black Opal Distro