According to Google "A Yixing Zisha teapot is a highly prized, unglazed Chinese teapot made from special purple clay (zisha) from Yixing, Jiangsu Province, known for its porous nature, excellent heat retention, and ability to absorb tea flavors over time, enhancing the brew's taste and aroma, making it a favorite for traditional tea ceremonies and valued for its artistry and craftsmanship. These teapots develop a unique patina, becoming more seasoned and valuable with each use, and can range from affordable daily items to extremely expensive collector's pieces."
