The sentence “Wo-Chien can be alloyed with metals,” in a paragraph from Pao Tsang Lun quoted in Chapter 8 of Pen Tsao Kang Mu, was once considered as evidence that ‘zinc’ had been known in China since the 10th century. Recently, this was challenged mainly because the same paragraph, but without the sentence about “Wo Chien,” was also quoted in K’ang Hsi Tzu Tien. Since the quotation in Pen Tsao Kang Mu is in general not identical with the original, it was then concluded that the sentence containing “Wo Chien” was not a part of Pao Tsang Lun, but an addendum by LiShih-chen. Reexamination of the 1iterature, however, brings us to a different conc1usion. In this study, evidence is given to show that Li Shih-chen might abstract and shorten the original, but did not add his own opinion to others ‘ in quotations. Moreover, the relevant paragraph quoted in K’ang Hsi Tzu Tien was proved to be copied from Pen Tsao Kang Mu. The authors of K’ang Hsi Tzu Tien omitted the sentence containing “Wo Chien” by mistake. Consequently, the existence of “Wo Chien” or “zinc,” in the Five Dynasty period can be confirmed. The absence of “Wo Chien” in the literature from Sung to ear1y Ming dynasty is also discussed.