Case: Cholelithiasis, the formation of gallstones. Surgical removal of gallbladder was done called cholecystectomy. Gallstones are piece of solid material forming in the gall bladder. * Cholesterol stones. These are usually yellow-green. They're the most common, making up 80% of gallstones. * Pigment stones. These are smaller and darker. They're made of bilirubin. Symptoms: * Pain in your upper belly, often on the right, just under your ribs * Pain in your right shoulder or back * An upset stomach * Vomiting * Other digestive problems, including indigestion, heartburn, and gas