First, look at the color to distinguish between true and false.

Tortoise shell is white, ivory-white, brown-yellow, with bright and clean appearance and pearl-like luster. The fake tortoise shell is made of white stone or broken shell powder or white stone powder with glue. It is flawless, white and dull, and its surface is polished and shiny, which is unnatural. The delicate surface texture of pearls represents their growing years in the deep sea. True pearls are delicate, slightly transparent, and as golden as milky white, while fake pearls are white and dull.

Second, look at the texture to distinguish between true and false.

Dragonflies grow naturally. If you carefully observe whether the lines are natural, the lines of the two dragonflies are the same. Its mineral structure is mainly aragonite, which is layered, with a single layer thickness of 0.5- 1.5mm and clear and dense layers. There is no natural growth line in the false tortoise shell and no obvious layered structure under the magnifying glass.

Third, look at the weight to distinguish between true and false.

The density is 2.70g/cm? The hardness is generally 2.5-3.0 degrees, and some of them can reach 4 degrees. Try to weigh it by hand. If it feels heavy or light, it may be unnatural.

Fourth, look at the cracks to distinguish between true and false.

There must be cracks on the old cockroach, and the thickness, direction and length of the cracks are disorderly and inconsistent. Under the magnifying glass, you can see that the crack and its surroundings are yellow.

Fifth, look at the size to distinguish between true and false.

Due to some conditions at that time, the size, roundness and weight of the old dragonfly were different, and there were certain differences, which could be distinguished with the naked eye. The size, roundness and weight of fake beads are mostly the same, which often gives people a sense of uniformity and perfection.

Extended data:

History of cockroaches:

In ancient China, it was regarded as a kind of wealth.

The name Zhuan Shu Da written by Fu Sheng in the Eastern Han Dynasty was first seen, which recorded a story that Zhou Wenwang was imprisoned here by Shang Zhouwang, and he traded his name for Zhou Wang and a palindrome king in his three lives.

The beads worn by second-class officials in the Qing Dynasty were made of dragonflies. In Tibetan esoteric Buddhism, monks and lamas also wear dragonflies as prayer beads to recite scriptures.

Buddhist monks all over the world should practice Guanyin Bodhisattva with beads made of bamboo slips. It is even said that bamboo slips have more than twice the merits and wisdom, and are the secret treasures of Buddhist practice.

References:

Baidu encyclopedia-Calligonum yuhua