IMO for the "price", I was quite happy with these studs.  But keep in mind..... the 1/3ct [listed on Amazon] is TOTAL Weight & not the individual weight of each earring.  Divide that by 2 & it equals the size of each stone.  Yes.... they are small but have a pretty, faceted sparkle.
And for those who know diamonds, the minimum color [on mine] was I - J and the min. clarity was SI2- I1.  Certainly not perfect but fine for the cost.

Hope this review was helpful.