What's the use of tortoise shells?

Tortoise shell used to be used for divination and sacrifice. Nowadays, it has become an important raw material of traditional Chinese medicine because it is rich in protein colloid and calcium salt. The solid colloid boiled by tortoise plastron is called tortoise plastron glue, which has good effect of nourishing yin and enriching blood and high economic value. Scarab and green turtle are two kinds of turtles, which have important ornamental value. In addition, the tortoise is a long-lived animal, which is called "the tortoise and crane prolong the year". As an auspicious thing, it is often used as a birthday gift and has important economic value.