This item uses natural stones. The string is made of elastic rubber. Cracked crystal: Approximately 10mm Inner circumference: Approximately 16mm [Cracked Crystal] Cracked crystal sparkles as the cracks reflect light. It is said to be a stone that brightens the holder's mood. The sparkle changes depending on the angle of the light, giving it a different appearance each time it moves. The color and pattern, the individuality of each stone is unique in the world. We hope you will enjoy these power stones casually, like a small amulet that accompanies you in your daily life. ◇ Due to the use of natural stones, there may be chips, scratches, and differences in color. We hope you will enjoy these aspects as well. ◇ Please refrain from purchasing if you are looking for the perfection of a mass-produced product, as this is a handmade item. ◇ There may be knots or cut ends of the string that are not tucked away, or are left as part of the design. ◇ The color of the product may appear different from the actual product depending on your device or environment. Please check the profile for bulk purchases.