This book describes the main industrial types of economic mineral deposits, the signs and indicators for recognizing them, and the criteria for evaluating them. The work of prospecting and the methods used in searching for deposits, and in exploring them, are treated at length. Full information is given on the techniques and systems of prospecting, on the sampling of mineral deposits, on the working down, testing, and controlling of samples. Methods of estimating and evaluating the ore reserves and economic value of deposits are discussed with practical advice; and the geological service of operational mines is described. Professor Kreiter's work is a textbook for students of the geological faculties of universities and mining colleges, specializing in the geology and exploration of mineral deposits. The author of this textbook, the late Prof. Vladimir Kreiter, was a distinguished and honored scientist, who at the time of his death held the chair of mineral deposits and exploration at the Patrice Lumumba Friendship University in Moscow. In addition to his teaching work, Prof. Kreiter carried on extensive research, his main work being devoted to the study of mineral deposits, the prospecting for and exploration of minerals and the structure of ore fields and deposits. Prof. Kreiter was the author of more than 100 published works, many of them well known abroad as well as in the USSR. In addition to the present volume, they included The Structure of Ore Fields and Deposits, Semi-metallic Deposits of Central Asia, and The Behavior of Gold in the Oxidation Zone of Pyrite Deposits. His books enjoy great authority with the teachers and students of geological faculties.