The discovery of minerals beneath our feet has transformed our species. Ochre first prompted humans to express themselves in art; tin and copper helped instigate the Bronze Age and later the Industrial Revolution; silver kick-started the engines of global trade. Each of these substances generated a leap forward in technology, each one opened the imagination a little further - and each one brought with it a cache of unexpected dangers. Under A Metal Sky begins and ends in Philip Marsden's homeland of Cornwall, one of the world's great geological hotspots.Travelling eastwards into Europe, he examines how the extraction of peat propelled the Netherlands to world prominence but also imperilled its very existence. Continuing on up the Rhine by barge, into the heart of the continent, he uncovers more stories of potent and tempting resources, from iron-rich meteorites to radium and mercury, and the gold-bearing mountains of Georgia. At the same time he explores precious seams of ideas, from science to alchemy, mysticism to ecology - and those questing souls who pursued them, likeParacelsus, the Habsburg Emperor Rudolf II, Goethe,William Blake and Marie Curie. Rich with revelations, Under A Metal Sky traces the dazzling achievements and dark consequences of our ability to extract what we want from the earth, and presents a fascinating new perspective on European history and on our troubled relationship with the natural world.