Pyu stone plate BU529. Ancient Central Burma. underthebo November 28, 2016 Pyu stone plate BU529. Small grey schist stone tray. Sourced at Beikthano, one of the 12 known Pyu city states. Ancient Central Burma. Circa 6th-9th century. Diameter: 16 cm x 2.5 cm high. 486 gr.