Black Pigment Gallstones : Appearance

Black Gallstones - Appearance: They are small, usually 0.2 to 0.5 cm, and rarely > 1.5 cm in size. They often occur in large numbers. The cholecystectomy specimen shown here had more than 400 black pigment stones. They are shiny dark green to black in color. They have mulberry-like or irregular shape with spiculated or molded contours, hard consistency, and are difficult to crush between thumb and index finger, unlike the brown pigment stones.