Which of us did not admire in childhood the unique patterns that appeared in the tiny window of a kaleidoscope? One had only to slightly turn the magic tube, and the previous picture was replaced by another, even more amazing one, then it was replaced by a new one, and after it the next one was already in a hurry to appear before our eyes... It was not by chance that we remembered this simple toy: the book that you now hold in your hands - also a kind of kaleidoscope of curious events and facts, ancient legends, useful information, curiosities and other entertaining materials related to the unusually interesting world of metals. When you leaf through the pages of this book, many things will pass before you, as in a kaleidoscope paintings from which you will learn about the secrets of the masters of antiquity and the metallurgical plants of the future, about how in the 18th century a wandering “musician” found out the secret of smelting crucible steel and how the mysterious alloy “ferrosilicon” appeared in our days, about violins made by a remarkable Russian metallurgist D.K. Chernov, and the “mistake” of the famous Norwegian traveler Thor Heyerdahl, about the “tricks” of platinum and the “grievances” of the bronze Robin Hood, about cucumbers “stuffed” with iron, and vanadium extracted from ascidians, about the “rubber” alloy and “glass” metals, about the rainbow on steel and sugar with molybdenum... However, is it necessary to retell the contents of the book to you if you have a kaleidoscope in your hands?..