Inner diameter: Approximately 18.5cm Prehnite is a stone that looks like a muscat grape. It is also called "grape stone" and is characterized by its pale yellowish-green color. Its healing color attracts many people. With 14mm beads, it has a strong presence. *There may be slight differences in color, shape, and size. *Since it is a natural product, there may be fine scratches. Other items are also available. If you purchase multiple items together, we will combine the shipping costs! Please let us know in the comments first.