It measures 8-10.9mm x 10.8-13.4mm. Inner circumference is 16cm. Adjusting the inner circumference smaller is free, but increasing it to 17cm is +100 yen, and 18cm is +200 yen. ☆ Amethyst's Energy ☆ Protective effect Inner peace Strengthening intuition Enhancing creativity ☆ Recommended for those who ☆ Seek inner peace Need creative inspiration Want to relieve anxiety Want to cultivate intuition ※ If you wish to purchase multiple items, we will discount 100 yen for each item after the second one. ※ Immediate purchase is OK ^o^ We will prioritize those who purchase immediately, even if comments are in progress. ※ There may be inclusions and dents unique to natural stones. Please understand this as a characteristic of natural stones.