RT Book, Section A1 Kasper, Dennis L. A1 Fauci, Anthony S. A1 Hauser, Stephen L. A1 Longo, Dan L. A1 Jameson, J. Larry A1 Loscalzo, Joseph SR Print(0) ID 1128787000 T1 Cholelithiasis, Cholecystitis, and Cholangitis T2 Harrison's Manual of Medicine, 19e YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9780071828529 LK accessmedicine.mhmedical.com/content.aspx?aid=1128787000 RD 2024/03/29 AB There are two major types of gallstones: cholesterol and pigment stones. Cholesterol gallstones contain >50% cholesterol monohydrate. Pigment stones have <20% cholesterol and are composed primarily of calcium bilirubinate. In the United States, 80% of stones are cholesterol and 20% are pigment.