Please note: This is a companion version & not the original book.Sample Book Insights: #1 The author was asked to sign a non-disclosure agreement by a man who said he had invented an electronic machine that sharpened blunt razor blades. The author was suspicious, but he was curious to hear the man’s story.#2 The Stone Age was a time when metal was extremely rare and highly valued, since the only sources of it were copper and gold, which occur naturally in the Earth’s crust.#3 The first people to discover how to make metals hard and soft were the ancient Romans. They discovered that if you put a piece of metal in a fire, it would get softer and stronger. This ability of metals to transform from a soft to a hard material must have seemed like magic to our ancient ancestors.#4 The crystalline nature of metals is hidden from us because metal crystals are opaque. They look like crazy paving, and inside those crystals are squiggly lines - these are dislocations, which are defects in the metal crystals. They are useful because they allow the crystals to change shape.