Colour of gallstones

Stones containing proteins are almost only formed inside gallbladder!There is at least a little bit of bilirubin (yellow/red/brown) or Biliverdin (green/blue/black) inside of every stone. That is the reason why cholesterol stones are not white, but may be of any color.

The same is true for every other stone. Most stones are green, and that means that they contain some Biliverdin (blood pigment).Those 7 colors: white, yellow/red/brown, green/blue/black can produce any other color.Common Bile Pigments:Bilirubin (linear tetrapyrrole)color: yellow/red/brown.Source: liverBiliverdin (linear tetrapyrrole)color: green/blue/blackSource: oxidation of bilirubin

Gallstones have different appearance, depending on their contents. On the basis of their contents, gallstones can be subdivided into the two following types:

• Cholesterol stones are usually green, but are sometimes white or yellow in color. They are made primarily of cholesterol.


• Pigment stones are small, dark stones made of bilirubin and calcium salts that are found in bile. They account for 20 percent of gallstones. Risk factors for pigment stones include hemolytic anemia, cirrhosis, biliary tract infections, and hereditary blood cell disorders, such as sickle cell anemia and spherocytosis.