Carefully observe the sand (turning sand) on the weathered crust of jadeite original stone and feel its texture by hand. If the sand is upright, evenly distributed, hard and rough, it is old jade. On the other hand, if the sand grains are not prominent enough, unevenly distributed, soft in texture and easy to fall off, then this is tender jade.

2. Water splashing auxiliary method

Splash a small amount of water on the original jade shell. If the water penetrates into the shell quickly (the wet shell will dry soon), then this is a tender jade; On the other hand, if the seepage velocity of water is slow (wet skin dries slowly), it is old jade. Its principle is mainly due to the different structural compactness of old and young jadeites.

The structure of old jadeite is very dense, the spacing between crystals is very small, and water is not easy to penetrate into jadeite. Most water molecules can only stay on the surface of jadeite and disappear slowly, so it takes a long time to dry after sprinkling water on the surface of jadeite. However, the structure of young jadeite is loose, and the gap between crystals is wide, so water can easily penetrate into jadeite, leaving fewer and fewer water molecules on the surface of jadeite, so it is observed that the wet jadeite surface dries quickly.

3. Method of observing fog layer

Observe the fog layer near the weathered crust of jadeite original stone at the jadeite incision. If the fog layer is thin (about one finger wide or narrower), it is the original jade stone. If the fog layer is thick (more than two fingers wide), then this is a young jadeite stone.

In a word, the above methods for judging the quality of jadeite products, rough stones and rough stones are simple and easy, which have high reference significance in the actual jadeite trading and are a summary of the experience in the field of jadeite trading for centuries.

However, the germplasm characteristics of jadeite are ever-changing, and any method can't cover everything, so it is inevitable to generalize. In practice, we should use it flexibly, adopt a variety of different methods at the same time, and make the most comprehensive, objective and reliable judgment with rich personal practice.

Extended data:

Quality of jadeite:

1. Planting water: namely planting ground and water head. Generally speaking, the head of planting land is proportional. Plant well, grow old, have a good head, and vice versa. Planting refers to the structural texture of jadeite, and the fine texture and dense structure are the best. Water head refers to transparency. The higher the transparency, the higher the value. However, oil-green species seem to be influenced by color. Although the head looks good, its value is limited.

2. Color: "Color difference is one point, the price difference is ten times", "Red and yellow are expensive, emerald is green, and jade is expensive" are the characteristics of jade valuation. Generally, positive green is the best, followed by spicy green, yellow-green, blue-green and other values, as well as red, yellow, purple and black (dark green).

3, carver: machine carving, hand carving, the spirit of the object is completely different, the value is naturally different. Master's work, by going up one flight of stairs, a carving trade union, is naturally more valuable.

4. Size ratio: Although the above indicators are all good, they are small in size, uncoordinated in proportion, limited in value, appropriate in size and coordinated in proportion, which are called "positive piles" and thick piles, and are also the basis of high value. As for the uncoordinated proportion, round and thick piles, they are all called "eccentric piles" or "strange piles" In most cases, the value of princess bracelets of the same quality is lower than that of safety bracelets.