Made in Japan. K18 product. This is a pendant top featuring a square-cut indigoite, a rare natural gemstone. Indigoite is a rare gemstone within the blue tourmaline family, known for its deep and mysterious blue color. Among tourmalines, it is considered highly valuable, second only to Paraíba tourmaline. Its unique indigo blue color has an appealing quality that evokes intelligence and calmness, and is highly regarded. Stamped with K18. Stone size: Approximately 3mm Material: K18 yellow gold, indigoite 0.15ct The bale has an inner diameter of approximately 3mm and is oval-shaped.