MA Zhaozeng, JIN Lianji, and YIN Xiulan, Formation of Black Patina on Bronze Mirrors Caused by Humic Acid, J. Univ. Sci. Technol. Beijing, 4(1997), No. 2, pp. 38-42.
Cite this article as:
MA Zhaozeng, JIN Lianji, and YIN Xiulan, Formation of Black Patina on Bronze Mirrors Caused by Humic Acid, J. Univ. Sci. Technol. Beijing, 4(1997), No. 2, pp. 38-42.
MA Zhaozeng, JIN Lianji, and YIN Xiulan, Formation of Black Patina on Bronze Mirrors Caused by Humic Acid, J. Univ. Sci. Technol. Beijing, 4(1997), No. 2, pp. 38-42.
Citation:
MA Zhaozeng, JIN Lianji, and YIN Xiulan, Formation of Black Patina on Bronze Mirrors Caused by Humic Acid, J. Univ. Sci. Technol. Beijing, 4(1997), No. 2, pp. 38-42.
The formation of black patina caused by soil humic acid under different conditions has been studied,and the black, grey and brown shiny surfaces prepared in laboratory have been analysed. The formation of tin-rich shiny black surface on mirrors was the product of the soil corrosion of the bronze mirrors. It is formed by reaction between the alloy and the humic acid in soil, and leaching of copper and lead oxides through a long period of time when the mirrors were buried under the ground. A dense cormsion-resistallt layer on the bronze mirrors consisted predominantly of stannic oxide.