A gall bladder calculus analysis using automated Fourier Transform Infrared (FTIR) spectroscopy is an advanced laboratory test designed to identify the exact chemical composition of gallstones. When a gallstone is extracted, it is placed into an automated FTIR analyzer, which shines infrared light through the sample. Because different molecular compounds absorb infrared frequencies uniquely, the instrument generates a distinct spectral fingerprint. This analysis precisely determines whether the stone is composed predominantly of cholesterol, pigment (bilirubin), or a mixed composition. Understanding the stone's makeup helps physicians uncover underlying metabolic causes and tailor effective, personalized recurrence prevention strategies.