Particular specification:
* Fe 3 content (%): ≥ 95
* Reduction (contrast with standard): da -0.5~0.5; dB -0.5~0.5
* Tinting strength(contrast with standard): 98-105
* Volatiles under 105:  ≤ 1.0
* Water soluble matter(%): ≤ 0.5
* PH of aqueous eztract solution: 5~8
* Oil absorption (g/100g): 15~25
* Residue on sieve 45un(%): ≤ 0.10
* Productivity: 6500 T/year