Used as a reference material in analytical chemistry for the accurate determination of iron content in various samples. Commonly applied in environmental testing, industrial quality control, and research laboratories to calibrate instruments such as atomic absorption spectrometers (AAS), inductively coupled plasma (ICP) spectrometers, and UV-Vis spectrophotometers. Ensures precision in measuring iron concentrations in water, soil, biological tissues, and metal alloys. Also utilized in the preparation of working standards for routine analysis and in method validation processes.