More than half of the world’s petroleum is found in carbonate rocks — for example, in the Middle East, the former USSR and in North America. These rocks show a bewildering diversity of grains and textures, due in part to the wealth of different fossil organisms that have contributed to carbonate sedimentation, and in part to a wide variety of diagenetic processes that can radically modify textures and obscure the depositional fabric. Careful petrographic study with a polarising microscope is a key element of any study of carbonate sediments — as a companion to field or core logging and as a necessary precursor to geochemical analysis. This atlas, which illustrates in full color a range of features not attempted in any general textbook, is designed as a laboratory manual to keep beside the microscope, and as an aid to identifying grain types and textures in carbonates. It will appeal alike to under-graduate and graduate students and to professionals in teaching institutions, research laboratories and industry. A Color Atlas of Rocks and Minerals in Thin Section — W. S. MacKenzie and A. E. Adams