Price listed is for twenty flat back stones. These are approximately 8mm Rianbow stones. These are lightly faceted with flat gray foil backs. These stones came in with a dusting of powder which I assume is to lesson any scratching during shipping. The manufacturer referred to these as 8mm. However, they measure out at about 7.7mm. These are much prettier in person. Depending on the angle or the light they show as mostly pink or green and occasionally blue and purple. THE COLOR MAY VARY FROM ONE BATCH TO THE NEXT.