Bronze mirror is better.
Bronze mirrors are the most popular means to exorcise ghosts and evil spirits, whether in the past Ching-Ying Lam series of zombie movies or in real life. Its concrete method is to hang a mirror at the top of the door cap or the root of the window of the house door to avoid ghosts and exorcise evil spirits. This kind of mirror is commonly known as "demon mirror".
Here's a problem. Why did the ancients use bronze mirrors instead of mirrors made of other metals to exorcise ghosts?
This will start with the characteristics of copper. Copper not only has good light transmission and refraction characteristics, but also has a crisp and distant shocking sound. In addition, the color is golden and bright, which is similar to the color of gold, so it won the favor of the ancients. Everything made of copper is regarded as the essence of things, and there are supernatural methods. Mirrors naturally became a powerful tool for ancient people to exorcise ghosts and evil spirits.
Using mirrors to shine on demons and exorcise ghosts has a long history among the people. The magic mirror originated from the worship of mirrors in ancient times, and the earliest magic mirror appeared in the Han Dynasty. According to Longjiang, "Emperor Xuandi of the Emperor Gaozu of Han Dynasty has a precious mirror, such as five rhenium coins, which are often rewarded." Ge Hong, a representative of Taoism in the Eastern Jin Dynasty, pointed out in Bao Puzi: Everything in the world grows old, and after a long time, it will have spirituality and magical powers, and their spirits can be transformed into human forms and worship people. But they can't change their true shape in the mirror, when the mirror reflects their true colors. Therefore, Taoist priests must wear a nine-inch mirror of Fiona Fang when they enter the mountains to cultivate monasteries, so that ghosts can't get close to it. When they reflect in the mirror, they turn around and run away in fear.
In this way, the mirror has become a magic weapon for Taoist priests to avoid ghosts and exorcise evil spirits. However, the Taoist magic mirror needs to be accompanied by corresponding inscriptions (spells) to enhance the magic of the mirror. For example, the unearthed Tang Dynasty cultural relic "Twenty-eight bronze mirrors" is different from ordinary bronze mirrors in both shape and inscription, and is divided into five circles from the inside out. Carve the square map, the four elephants in the east, west, north and south, the zodiac, the eight diagrams, the twenty-eight astrolabes and inscriptions in turn. Inscriptions are actually spells and things like that.
Even bronze mirrors are used in different ways in different places because of different customs. For example, in rural Jiangxi, mirrors are usually hung on the top of the lintel of the main entrance (front door) of the house. You can't hang it on the lintel of the back door, because the back door may be facing the front door of another house. If you do this, you will drive all the ghosts into your neighbor's house, and naturally you will be strongly dissatisfied with your neighbor and even fight.