One is to " listen to the sound", knock the bronze mirror with your hands, and distinguish the true from the false through the sound announced by the bronze mirror. Since the proportion of copper, tin, lead and other materials in the production of new and old copper mirrors is different, the sound announced is also different. The sound of the old bronze mirror is relatively low and mellow, while that of the new one is crisp and even sharp.

　　The second is " looking at the shape", observing the shape of the bronze mirror, and distinguishing the authenticity of the bronze mirror from the shape. In order to ensure that the bronze mirror can have a real and clear effect, when the ancients cast the bronze mirror, the size and radian of the mirror have a strict proportion. Generally speaking, a smaller copper mirror can see a relatively steep arc. A copper mirror over 20cm is basically a plane, and no significant arc can be seen. However, the arc of the new imitation copper mirror is not proportional to the size of the mirror. The arc of the large copper mirror is very large, and the arc of the small copper mirror is not naturally shortened. Therefore, the people and images reflected by the copy mirror are often unclear or even distorted.

　　The third is " rust identification". Bronze mirrors have been in the soil for thousands of years. The rust color is solid and natural, with clear layers. The rust on the new imitation bronze mirrors is made later. Many fake rust is painted with various glue and pigments, with low strength. So the rust that can be removed by hand is likely to be imitated.

　　The fourth is " smell". After touching the copper mirror with water, smell it by nose. The new copy of the copper mirror usually has the smell of sulfuric acid, alkali burning and copper smell. But the old bronze mirror generally has a kind of copper fragrance, which is the earth fragrance after the excavation. In addition, you can take a piece of copper rust and burn it with fire. Fake rust will burn and produce thick smoke with the smell of chemical materials, while real rust will not.