Yachimun Tsuboya-yaki Yomitan-yaki Coffee Cup, Purple Glaze Purchased at the largest pottery fair in Okinawa Prefecture, held annually at Hotel Moon Beach in Onna Village. AI Features: Material: Yachimun Color: Purple glaze Design: Handmade, with a speckled pattern on the glaze. The mouth has an oval shape. Style: Rustic, and due to the characteristics of pottery, each piece has a unique texture, making it a one-of-a-kind work. [Size] Cup Height: Approximately 7.6cm Mouth Diameter: Approximately 7.7-8.1cm Foot Diameter: Approximately 4.5cm Weight: 236.5g Capacity: 150ml (80% full) ● There is a mark like the kanji "叶" (kanau - to come true) on the bottom of the cup, but the artist is unknown. (Photos 15, 16) AI Summary: ◆ The reason why purple coloration is considered very difficult in Yachimun (Okinawan pottery) is mainly due to the nature of traditional glazes and the severity of firing conditions. Even with current ceramic techniques as of 2026, purple is considered one of the "difficult colors to produce" for the following reasons: ・Unstable chemical reactions: Purple coloration usually uses manganese, cobalt, or copper, but these are delicate components that are prone to changing color to brown or black with slight changes in the amount of oxygen (oxidation/reduction) and temperature in the kiln. ・Compatibility with traditional raw materials: Yachimun traditionally uses glazes made from wood ash and local soil. Impurities contained in these natural raw materials can detract from the vividness of the purple, requiring advanced mixing techniques to achieve the desired purple. ・Individual differences due to climbing kilns: When firing in traditional climbing kilns, the temperature and flame exposure vary depending on the location, making it extremely difficult to consistently produce the intended purple color. ※ There is a 3mm-ish chip on the rim, but it is under the glaze and is considered to be from the manufacturing process. (Photos 12, 13, 14) ● If you don't mind that point, especially purple yachimun, I think it is a rare item. ※ There is no box, so it will be packed using cushioning material.