The author thanks Marco Leona, Scientist-in-Charge of the Department of Scientific Research at the Metropolitan Museum of Art for conducting fluorescence spectrometry on Wheel of Fortune and a valuable discussion of the research, as well as Silvia Centeno, Research Scientist at the Metropolitan Museum of Art, who performed Raman analysis on the watercolors and also contributed her insight. The phenomenon of the phosphorescing lithopone was originally discovered during the author's fellowship in the Sherman Fairchild Center for the Conservation of Works on Paper, funded by the Andrew W. Mellon Foundation. The author thanks all her colleagues for their ideas and support during the research of this paper, and special thanks to Rachel Mustalish for her assistance in editing this work.

2. Mentality: the buyer has to prepare goods in advance, and the new order price is slightly less willing to purchase in bulk; Because the seller's inventory is small, the manufacturer has no willingness to reduce the price of sales.Trend: The load of titanium dioxide enterprises is stable, the willingness to ship at low prices is not strong, and the downstream buyers place orders in the early stage to establish inventory, and the short-term supplementary orders after the holiday are less. Anatase titanium dioxide due to the overall volume of the market supply side is less, the space for quotation negotiation is small, and the focus of new orders will move up. It is expected that the titanium dioxide market today just needs to be closed, and the market trading atmosphere is relatively light.