It is the blue crystalline or viscous liquid. After encountering light, it changes from blue to green and finally to yellow. Insoluble in water, insoluble in ethanol, soluble in chloroform, ether, vegetable oil and volatile oil.

Test Items                               Specification

Appearance                    Dark blue liquid or crystal
Identification     It shows absorbance of maximum at 604-608nm
Freezing Point                                 ≥30°C
Water                                               ≤0.1%
Residue on Ignition                         ≤0.1%
Purity(GC)                                       ≥99.9%