Tanzanite is such a regal stone, full of colors ranging from blue to purple and including all of the lilac, lavender, and indigo hues in between.  These little 3mm studs are brilliant and sparkling, and are perfectly understated on their own, but work wonderfully as a second piercing earring, too. 

The post is centered on the back of the setting, making these studs reliable and effortless - exactly the kind of sparkle that I love to add to my day.