Xu Collection, Upper Volume Radical: Metal (jīn) Bo Kangxi strokes: 13 Page 1301, Entry 07 Gathering of Rhymes (Jiyun): Pronounced bo. It refers to thin gold. Correction of Popular Scripts (Zhengzitong): Gold bo is thin gold. It is made by hammering gold flakes separated by medicated paper; the gold becomes thin, but the paper is not damaged. The paper is initially brownish, but over time the color resembles dark gold. Originally, the character for thin was used, but common usage added the metal radical to form bo.