1, shape: General bloodstone keeps its natural shape, including goose egg shape and angular.
2. Stone skin: The cortex of bloodstone is extremely thin or slightly thick. The color of stone skin is mainly black, yellow, white and green. The cortex has single layer, double layer and three layers. The cortex is finer and softer than other excavated bloodstone. It is scraped lightly with a knife, and the knife feels smooth and slightly heavy, and the powder particles are fine and even. Under normal circumstances, except for some three-layered bloodstone, the general bloodstone has good permeability under the light, which can provide insight into its internal texture and color.
3, hue: to identify the true color of bloodstone, you should not observe it under the light, but observe it in the sun. Generally speaking, there are two types of silver-coated Jintianhuang. One is between the white bloodstone and the yellow bloodstone, with the muscle mass of Baitian Huangshi outside and the quality of gold and yellow bloodstone inside. White bloodstone mostly has a yellow heart. If there are many yellow hearts, it belongs to silver wrapped in gold. The other is white-skinned bloodstone. There is also a kind of "gold-wrapped silver" bloodstone, which is extremely rare.
4, texture: Tian Huangshi's texture is basically hidden with fine radish patterns as dense as a net, and it is dense and organized, such as peeling new radish, like cutting fresh oranges. The finer the muscle texture of bloodstone, the lighter and more transparent the color, the more obvious the radish pattern, so the radish pattern of Baitianshi is often the most beautiful. There is also a kind of bloodstone, the radish pattern is extremely hidden, extremely fine, extremely inconspicuous, and the color is also very pure and excellent, which is one of the most condensed bloodstones.
5. Lattice-cracked form: In ancient times, there was a saying that "there is no field without lattice". This is because most bloodstone is more or less cracked. However, the cracked lattice is not unique to bloodstone, but the cracked lattice of Tianhuang, and its color and shape are different. The cracked lattice of bloodstone has open lattice and dark lattice. The red squares of bloodstone excavated in the field, also known as "red tendons", are mostly brown or ochre yellow. The skinless bloodstone has a thick red grid. Black-skinned bloodstone and white-skinned bloodstone are also common, so it is difficult to hide when carving.
6, feel: another important feature of bloodstone is that the texture is warm, delicate and tender. All kinds of bloodstone, even white bloodstone or black bloodstone, in the light, the stone heart is yellow and red, and the treasure is brilliant. Although it is cold in winter, it is also warm and affectionate. Bloodstone is in the hand, and it feels greasy. It is not oiled all the year round, and it is not dry. Once it is rubbed, it feels oily.
7. Specific gravity: The specific gravity of bloodstone is between 2.6 and 2.65.