Quality level of the product
1).Appearance: Beads are clean, transparent,and free sub stantially from bubbles and foreign matters.
2). specific gravity: 2.23-2.5g/cm3
3).Indes of refraction: 1.5-5.5
4).Glass composition: Soda-lime glass.silica content is higher than 62%
5).Roundness>80%
　　Note：Besides above specification, can be still according to the tiny bead of the different grain, different scale of the advocacy's requirement, capacity.