These earrings are currently being worn by an 11 year old girl, who think they are great: the actual stone part appears to be about the right size for her ears, and I would imagine they would be a tad small for an adult's ears, but the posts are a little long for her ears if that makes any sense.

The stones have a bright little sparkle when reflecting light.  One thing to note on the product description is the earrings are described as "heart shape...round amethyst stud earrings" which requires a little more explanation: the stone is round, and the stud backer to the stone is heart-shaped.  In other words, don't expect a heart-shaped amethyst.  Overall, I would say these are a nice set of earrings for a young girl but not an adult.