Having decided to use gold as his creative medium, Wu set to work, using 99.99 % pure gold that lacked the silver or copper that goldsmiths traditionally add to make welding easier (but that in time cause oxidation, with the silver turning black and the copper green).
決定以黃金作為創作素材，吳卿投入相當多心血，不但使用九九九九純金為材料，並摒除傳統摻雜銀、銅等金屬為銲藥，因為摻雜銀、銅銲藥後，時日一久，作品容易產生氧化現象；銀變黑，銅變綠。