These are so nice. The stones are beauties. They sparkle like crazy. Diamond earrings couldn't be any prettier. The 4mm is equivalent to 1/2cttw; 3mm about 1/4cttw; and the 2mm is approximately 1/10cttw. These a are small earring with a big sparkle. There are so noticeable, I wear the 4mm  in my main piercings.  Normally, I prefer a bigger stud, but these little earrings really pop. They are set in nickel free silver. The post are sturdy and the backs fit securely to the earrings. Previously, I purchased a pair of the 2mm individually. I've shampooed and showered in them and they kept their beautiful sparkle.  Neither has the silver tarnished.

There are few sellers offering small CZ studs for a penny; along with a 6.95 shipping charge.  I purchased a couple of pairs of those, too. These are prettier, with better quality stones.