This is the TARDIS ring designed and sold by Etsy seller dtekdesigns. It looks like the door of Doctor Who's TARDIS (or any blue police callbox). The ring comes with a 1/4 carat total weight of diamonds and blue sapphires and costs $1,100 in sterling silver. A white, yellow or rose gold version will set you back $1,900, and titanium $3,000. Sadly, the ring is not available in uranium, which is a shame because I've always dreamed of my girlfriend gaining superpowers.
Keep going for several more shots, including what it looks like on a finger (it's smaller than it appears).