Identity (UV/VIS-Spectrum): passes test

Appearance: Black to dark brown-black fine powder, eventually with granular parts

Clarity of solution: passes test

Absorption maximum λmax. (buffer pH 10.0): 612 - 616 nm

Spec. Absorptivity A 1%/1cm (λmax; 0.02 g/l; buffer pH 10.0; calc. on dried substance): 400 - 510

Loss on drying (110 °C): ≤ 7 %

Suitability as indicator (for complexometric titration, ACS): passes test

Suitability as indicator (Reag. Ph Eur): passes test