In the industry, the crystal grading only ranks the third type of rose-like blue crystals produced in Sri Lanka. There are generally three first type 5A, one is the seed level, and the other is the fluorination level.
1:5A level, this is a level distinction in the industry.
AA grade: The whole blue crystal is flawless, and there are no visible artifacts on the surface such as cracks, smooth and delicate such as gems, fine perforations, and glass luster after polishing.
Grade A1: Very fine flaws, or fine natural inclusions, no more than 3 mm cracks. Polished with a matte finish.
Class A: There is a slight flaw, which is easily broken by the naked eye.
Class AB: There are large pieces of white, yellow and gray, with obvious cracks.
Grade B: There is a large area of ​​variegated color, a large number of cracks, and a sense of soil sand after polishing.
Grade C: The lowest level, the crack is obvious, the surface also has obvious impurities, and it is as rough as brick after polishing.
2: Blue crystal seed, this blue crystal grade used in the wholesale.
Bean species: surface matt, sandstone, weak effect.
Ink type: There are many impurities on the surface.
Ice: The surface is as clean as jade and free from impurities.
糯 species: the surface is as clean as a gemstone, no impurities, delicate as a gemstone, rich in color such as glutinous rice juice.
Static water dragon stone species: translucent as a gemstone, extremely rare.
3: According to the illuminance, the term fluency itself does not mean transparency but brightness. The finer the texture, the brighter the polished. This is the national gemstone testing standard. The bigger the number, the better the quality. The blue crystal is used for the jewel level, and the lowest level of the jewel is 1 minute.
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