The natural materials used to make eyeglass frames include tortoiseshell, special wood, and animal head horns. Generally, wooden eyeglassses frames and horn frames are rare, and tortoiseshell eyeglassses frames are common.
1. Tortoiseshell frame
It is a frame of eyeglassses made from tortoiseshell shells produced in the tropical sea, and is mainly produced in the West Indies. Its advantages are light weight, beautiful luster, easy processing and polishing, plasticity when heated, jointing when heated and pressurized, no irritation to the skin, and durability and preservation value.
Among all kinds of eyeglassses, it is a high-end product and is very popular among middle-aged and older male wearers. Its disadvantage is that it is easy to break compared with materials such as celluloid, but it can be bonded and repaired after breaking. When displaying on the counter, place it in water to prevent it from drying out. Do not use ultrasonic cleaning during maintenance, otherwise it will become whitish and lose its luster. Since tortoiseshell is a prohibited animal in the ocean, the production is small and the price is high.
2. Horn frame
Frames with horns as eyeglassses frame material were not common until the beginning of the 21st century.