An ATR-FTIR study was conducted on HAp powders. FTIR spectra were obtained in ATR mode using a Nicolet iZ10 spectrometer (Thermo Scientific, Waltham, MA, USA), covering the range of 600-4000 cm⁻¹. Each spectrum consisted of 32 scans and was recorded at a resolution of 4 cm⁻¹. For data presentation, the FTIR spectra were exported as ASCII files to OriginPro 2021.