Figure 3.

Illustration of a typical FT-IRIS spectrum of mineralized vibrissae. The bands associated with the vibrations of organic bonds from proteins are shown as amide I (C=O stretch) centered at 1650 cm⁻¹, amide II (C-N stretch and N-H in-plane bending mode) centered at 1550cm⁻¹, amino acid side chain vibrations due to C-H bending motions (overlapping bands 1500–1360 cm⁻¹) and amide III combination band centered around 1250 cm⁻¹, and absorbances from carbonated calcium phosphates as phosphate ν1, ν3 (1200–900 cm⁻¹), and carbonate ν2 (890–840 cm⁻¹).