Thank you for viewing. Stone Name: Sodalite Stone Size: 12mm Inner Diameter: Approximately 16cm Condition: Only tried on Sodalite is also known as the "stone of intelligence" and is said to be effective in enhancing thinking and concentration skills. It can also be used as a good luck charm for students, exams, interviews, and matches. Purchased at Tida Stone in Okinawa. Please note that due to the nature of natural stones, there may be small chips, dents, irregularities, and cracks. As this item has been handled by a person, please understand this before purchasing.