There are three inherent characteristic absorption peaks of 3184, 3232 and 3310cm -1 in the infrared spectrum of flame fusion grown ruby which has been heat treated at 1100°C.
天然红宝石的红外光谱通常有硬水铝石的 2 1 1 0 cm-1和 1 980 cm-1特征吸收双峰 ,或其它内含物的吸收峰 ;经 1 1 0 0°C热处理焰熔法合成红宝石的红外光谱均有 3 1 84 ,3 2 3 2和 3 3 1 0 cm-13个固有的特征吸收峰。