The sixth edition of "Data of Geochemistry" is a compilation of stable isotope fractionation factors for geochemical interest, edited by Michael Fleischer. It includes chapters written by various scientists, each focusing on their specialty. The chapter on stable isotope fractionation factors, authored by Irving Friedman and James R. O'Neil, presents data on isotope fractionation factors for hydrogen, carbon, oxygen, and sulfur. The data are plotted as a function of temperature and include discussions on terminology, isotope standards, and the relationship between different isotope standards. The chapter also provides detailed information on the fractionation factors, including equations relating different standards and the use of logarithmic and delta values to express isotope fractionation. The chapter includes references to various studies and provides a comprehensive overview of the current state of isotope geochemistry. The data are presented in a convenient format, with figures and tables illustrating the fractionation factors for various mineral-water and mineral-mineral pairs. The chapter also addresses the importance of accurate isotope standards and the challenges in comparing data from different laboratories. The compilation serves as a valuable resource for geochemists and other scientists working in the field of isotope geochemistry.The sixth edition of "Data of Geochemistry" is a compilation of stable isotope fractionation factors for geochemical interest, edited by Michael Fleischer. It includes chapters written by various scientists, each focusing on their specialty. The chapter on stable isotope fractionation factors, authored by Irving Friedman and James R. O'Neil, presents data on isotope fractionation factors for hydrogen, carbon, oxygen, and sulfur. The data are plotted as a function of temperature and include discussions on terminology, isotope standards, and the relationship between different isotope standards. The chapter also provides detailed information on the fractionation factors, including equations relating different standards and the use of logarithmic and delta values to express isotope fractionation. The chapter includes references to various studies and provides a comprehensive overview of the current state of isotope geochemistry. The data are presented in a convenient format, with figures and tables illustrating the fractionation factors for various mineral-water and mineral-mineral pairs. The chapter also addresses the importance of accurate isotope standards and the challenges in comparing data from different laboratories. The compilation serves as a valuable resource for geochemists and other scientists working in the field of isotope geochemistry.