About-Gallstones also called cholelithiasis are pieces of solid material that form in the gallbladder, a small (about 3 inches long and 1 inch wide), pear-shaped organ on the right side of the abdomen, just below the liver.
Types of gallstones Cholesterol gallstones - The most common type gallstone, generally yellow-colored and is composed mainly of undissolved cholesterol. Pigment gallstones- Generally dark brown or black colored stones develop from bilirubin.
Causes-
The exact reason is not clearly understood. It may be due to having too much cholesterol or bilirubin in the bile. Probable risk factors are A family history