Under a Metal Sky: A Journey Through Minerals, Greed, and Wonder

by Philip Marsden

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.

Genres: Nonfiction, History, Science, Nature, Travel

352 pages, Hardcover

Published November 4, 2025

About the author

Philip Marsden is the author of a number of works of travel writing, fiction and non-fiction, including The Bronski House, The Spirit Wrestlers and The Levelling Sea. He is a Fellow of the Royal Society of Literature and his work has been translated into fifteen languages. He lives in Cornwall.

Reviews

[Francis Pellow · Rating 4 out of 5]

very interesting book of the week adaptation on bbc radio 4. Looking forward to hearing Philip speak on the subject soon and maybe even reading the whole book.

[Debby Binns · Rating 3 out of 5]

I listened to the abridged version of this on BBC Sounds and whilst the subject matter isn't something I'm hugely interested in I really enjoyed this book. I also went to hear Philip Marsden talk in Falmouth about the book. A couple of fascinating facts about Cornish mining, along with moissanites, were the take aways for me!

[Vansa · Rating 5 out of 5]

We should all be grateful for Marsden’s early interest in rocks, that ended up being a lifelong love, we wouldn’t have this lovely book without that! While he does give you the ‘greatest hits’ of all the metals he’s writing about, he also digresses in surprising ways. The chapter on iron, for instance, while he writes about the expected uses of iron, has an unexpectedly moving section on ochre. Ochre, a ferrous rock, is derived from iron-the most common element on earth, that leaches into soil, water, and in rocks. Most multicoloured striations in canyons and gorges that have made Instagram stars of rocks, can be attributed to the astonishing variety of hues ochre takes where it’s found. Marsden muses on the early humans who realized that you could mix this soft colourful clay-ey substance with a liquid, and it would form a paste that you could apply onto a surface-it seems obvious but in terms of what it implies for the evolution of thought, it’s like the monkey tossing up a bone that turns into a spaceship. The earliest uses of members of the homo species using ochre paste can be dated to nearly 300000 years ago in parts of Africa-entire ochre toolkits with bones carved to pencil-like points with ochre pigment on them, shells showing signs that stones were crushed with the ochre being filtered out and stirred several times, indicating that a particular consistency was desired. Cave paintings are something that tend to move me to tears any time I read about them-the earliest ones found so far date to nearly 35000 years ago, in Indonesia and Europe. Homo sapiens migrated out of Africa around 90000 years ago, and it’s so incredible to think that in just 50000 years, humanity realized there was more to life than food and the survival of the species, and that the human mind could be used for something apart from existence-we
could imagine something that wasn’t right there in front of us. That’s an extraordinary leap, and I
understand the conceit of Kubrick and Clarke, of a monolith that flipped a switch in the homo species brain that led to the dawning of consciousness. We don’t have much evidence of what life in the Stone Age was like, but anthropologists extrapolate from the way ochre was being used, and all the processes that went into that. We have no idea why the first person who decided to start painting did that! (Writing wouldn’t be invented till nearly 20000 years later, and even then for many millennia it wasn’t for works of imagination, it was mostly grocery lists). Cave paintings don’t really seem to have a particular evolutionary use-they’re not a tool for self defence or hunting, or cultivation of a crop to eat, which were -they’re there because someone thought it would be nice to leave a record of animals they hunted, or a river they crossed, in a place where it wouldn’t get washed away, and a place other people also knew of-implying awareness of a sense of self and the urge to document individual experience ( we’ve clearly always had annoying people wanting to show you photos of their holidays! But without these early annoying humans, you wouldn’t have works of art. On the other hand, also no Instagram influencers but you can’t always get what you want!) There’s enough evidence that humans actually traveled some distance to find the ochre to make their little drawings, as geological analyses show that the areas surrounding some of these caves don’t have ochre for miles, or for particular shades, or varieties of ochre that had sparkly bits to add a dash of glitter ( mica or pyrites in the soil) where they would have had to swap things for it, possibly of a higher value.
“Ochre altered forever, our relationship with the earth. The dead rock underfoot yielded something miraculous, something striking and powerful, something that with conscious intervention that could be transformed and then be used itself for transformative effect. Some cosmic shift took place in that taction. nothing was the same again. Change had always been external, day and night, weather and seasons, rivers and tides, life and death. Now with the use of its own material, the Earth could be subtly remade and modified and abstractions created. Dirt was made precious, stones did tricks, rock became transcendent.”

His chapter on bronze explores all the familiar ideas we’re used to, this miraculous alloy that was put to so much use, each a leap forward to taking the world to where it is now, including changing warfare to a more large scale version-for its time. Most of this are things you already know, but he also writes of one of Europe’s earliest bronze artefacts, found buried in a field in Germany-the small Nebra sky disc, inlaid with images that represent the sky. It’s one of the earliest representations of the sky to be found anywhere, something that could be a bit of a guide for seasonal activities, like planting crops. The Bronze Age, as Marsden puts it, was a period of movement and connection, globalization in embryonic form. Pre modern interconnectivity was all knit by this one resource-the tin for this disc was from Cornwall. The finding of this artefact is as quirky as the little disc itself, it was found in a farm by an amateur detectorist, who didn’t really know its worth, and you get some insights into the world of underground collectors who bypass museums. Curators of state museums have their own networks, apparently, and the curator of the state museum wasn’t going to let a treasure like this rot in some billionaire’s private vault. He managed to track down the owner, pretending to be a collector, and it’S described like a heist movie, with the curator meeting the shadowy owner who taped the disc to his waist, under his shirt for the meeting. I love Marsden’s description of actually seeing the disc in the British Museum-his initial reaction is very human, when you’re confronted by something from antiquity-Is that it? It’s only when you think about what it represents, and how very old it is, that it’s breath-taking. Crafted around 1600 BCE, this disc combines the Bronze Age’s main anxieties-the mysteries of the cosmos, long-distance trade and managing the weather. (When I first saw the Cyrus Cylinder for instance, while I thought it was intricate and beautiful, the import of what it means, didn’t really strike me, till I thought about what the text really meant-one of the first declarations by a ruler that he respected all the faiths of his conquered peoples and would rebuild all their temples-broad minded by even today’s standards) Marsden writes of the belief in antiquity of the correspondence of sky and earth, and that the heavens reflected all the material the earth was made of ( not too outlandish when you think of it). In the Kallevala, the Finnish epic, the sky is metal made by skillful creators. In Pharaonic Egypt, the sky is metal, pricked with little holes and you can see pinpricks of light shine through in the night. And sometimes, little bits break off and drop to earth as meteorites, from where you can get metals. While the forms these beliefs take could differ in interpretation, they’re all united by the idea that the earth and the sky are a whole and the movements of both and materials are reflected in each other. People must have realized that from certain places, like specific hilltops, and at particular times of the year, the sun would rise in a
predictable pattern and the burial mound where the Nebra Disc was found, was one of those places.
Clearly at a time when so much of the natural world was so inexplicable, people still wanted to try to make some sense of it, and arrive at a pattern that they could use to their advantage, and replicate the sky they could see, onto a part of their corner of the earth.
I’ve read so many books on radium and all of them are wonderful-as Marsden points out, no other
element is as emblematic of the earth’s ability to provide us with sustenance and mass scale
devastation. You still discover things you didn’t know though, and some of the hidden human costs- Marsden visits a town in the Czech Republic that runs a radon resort; a supposed wellness cure that people seem to find effective. The town hides a secret though-during WW2, captured Soviet POWs were put to work mining radium, and after it, captured Germans were. Under the Soviet Union, it also served as a prison camp for dissidents-not just Czech, but all over the Soviet Union. Marsden muses on all the lecturers, journalists, musicians, poets, and everyone else who would have worked in the mines, for the Soviet nuclear programme. This was a secret Soviet enclave for decades, that was then closed. All hidden by the now idyllic seeming town and health-enhancing radon! You can’t really write about metal without writing about alchemy, and Marsden has evocative descriptions of Rudolf of Habsburg’s court of alchemists and scientists-in their search for primordial material and the one basic truth from which all things come, alchemists did end up stumbling upto scientific discoveries-gunpowder, for instance, was an alchemical experiment gone wrong ( or right), Newton was a committed alchemist whose knowledge of metals helped him as Master of the Mint. He starts with describing the Emerald Tablet of Hermes Trismegistus, that was translated into English by Newton again, with its maxim of “as above, so below” being a guiding principle of alchemists. His perspective about alchemists is interesting, and made me reconsider them- instead of casting them as kooks obsessed by greed and immortality, which is how I’ve always thought of them (probably because of the utterly evil priest Frollo in Hunchback of Notre Dame), Marsden writes of their research as stemming from a desire to lead a life of scientific inquiry and a search for knowledge of how things came to be, they were practically proto-theoretical physicists. This was a time when most of the Europe still believed that the sun revolved around the earth, so while some of their ideas might have been fanciful, it’s difficult to utterly dismiss alchemists as cranks-one could as easily dismiss theoretical physicists working on Grand Unified Theory! Also the tradition of hermetic thought emphasized on the connections between things, not the hard distinctions that taxonomy and classifications insisted-a unification of mind and body , the natural world and the human one. There are still some stores that sell
crystals and stones, and Marsden visits one, where he sees a moldavite, and proceeds to tell its story. A moldavite is a type of tektite, that are hard glass objects formed during meteorite strikes-the heat generated when it’s rushing towards Earth causes sand and mud to liquefy and the droplets to rise to thousands of feet, before gravity takes over, and they fall to earth, solidifying to glass on their return journey, sometimes thrown hundreds of kilometres away from the strike site. The ones in parts of Bohemia, because of the copper and nickel content, are vivid shades of green, and named after what the Vltava is called in Bohemia, the Moldau. So an impossibly ancient object, from the outer reaches of the universe, travels to this little planet, and causes sand to change into glass in the sky and return to earth, all the while influenced by its properties of what it was like as a part of the earth. Hermes Trismegistus ( if he existed) and all the star scientists/alchemists/experimenters of Rudolf’s court would definitely consider this alchemy of the most sublime sort.

I know more about the economics of gold than a lot of people because my work requires me to analyse that. Knowledge hasn’t brought any understanding of why this metal should mean what it does though! Marsden makes a good stab at it, and reading it now was for me particularly apposite, given that gold prices have never been higher. There’s a flight to safety happening to gold as the most stable assets, only this time it’s not happening in areas that are the usual suspects, the Third World-it’s American investment banks and investors rushing to it! Humanity’s always had a strange relationship with gold- the Aztecs thought gold was the excrement of the sun, the Incas thought gold was the sweat of the sun. From the perspective of the sun-it can’t make gold. Fittingly, a metal like this requires an event of great power: the collision of supernovae create gold, and those particles , probably sparkling in the blackness of space travel at great speeds, some of which ended up on earth-most of it in the core. Gold is oddly heavy, but also soft, and you can shape it like no other metal can. Marsden describes how it can be hammered into a sheet of ultrafine thinness, moulded into shapes one wants, or pulled out into gold threads for filigree work, nearly 50 miles long. Given the effect it has on humans, it’s surprising it turns up quite late in the archaeological record: copper and meteoric iron are much harder to shape and work with but are in Mesolithic burial sites, 10000 years ago. When it does start appearing though, it’s already being shaped into grandiose, elaborate forms, that would be familiar to us even now-one of the earliest
gold hoards is in Bulgaria, 6000 years ago, in a burial site, that has nearly 3 kilos of gold objects,
everything you can think of ( including a solid gold proto codpiece. As I’ve said before, humans are weird about gold. And some body parts). It’s more gold in this one tomb than has been found at a single site anywhere else in the world dating to that time! Gold, from its entry into human consciousness has always been only for display of your social power-wealth and status. Nothing has changed about this, millennia later-neolithic tombs to Rolexes. Thucydides rued the pernicious effect of gold on human greed in the 6th Century BCE, and you continue to have accounts on similar lines.
“The king of metals, it presides over human life by channeling want. Not for an object, or a person, a time or a place, but for the possibility of all of them.”
AS beautiful a way to phrase why we chase this metal as any. In his quest to explore the quirkier stories associated with this metal, Marsden travels to the town of Svaneti in Georgia, nearby where the mythical Prometheus faces his punishment for bringing knowledge of fire and metallurgy to humans. It’s also possibly the origin of the story of Jason and the Golden Fleece-a local story goes that while panning for gold, locals would use sheep’s fleece to filter the water and leave them to dry, with the gold still in them! The area is known for its minerals, and during the Soviet Union, machines would come in to mine gold. Marsden meets a local eccentric who continues to pan for gold with a very appropriate nickname:Mackenna. He then proceeds to spend an oddly idyllic afternoon in the company of Mackenna, his friend and his dog, lazily panning for gold in the sunshine-for an act that stems from human acquisitiveness, it’s a remarkably laid back afternoon he describes! Probably because they don’t depend on it for their fortune anymore-as Mackenna tells him, he just continues to do it, because he always did. Just like we continue to value gold, because well always did.

[Mark Hartzer · Rating 4 out of 5]

The subtitle to this book is “A Journey through Minerals, Greed & Wonder”, which partially explains how the narration sort of jumps around.

Mr. Marsden has broken down his book into 13 chapters:
1.) Ammonite
2.) Ochre: An Introduction
3.) Tin
4.) Peat
5.) Bronze
6.) Silver
7.) Radium
8.) Aerolite (actually, meteorites)
9.) Mercury
10.) Copper
11.) Gold
12.) Lithium: A Coda
13.) Soil

Right away, you can see that this book is not, strictly speaking, about metals, as an ammonite is a fossil; ochre a pigment; peat a decayed plant matter; bronze an alloy; aerolite a meteorite; and soil is self descriptive. We also don’t have a couple of major metals like iron or platinum, so this is really not a book about metals.

Therefore, you are better examining the subtitle since this is not explicitly about metals. This is really a book about minerals; how and why we humans have extracted them; the damage the extraction process has caused to the Earth, its environment and people and finally; about how cool it is that the stuff made from stars just happens to be intrinsic to our lives.

But there are peculiar sections to each chapter where Mr. Marsden goes down a rabbit hole into explanations that don’t really shed much light on minerals and often just sort of appear as filler. Yes, I know who William Blake is, but is he really relevant to the subject at hand? And by the way, what exactly is the subject? It is often difficult to tell.

Odd, but often funny little interludes such as this one on p. 76 in the chapter titled ‘Bronze’: “‘Electrics!’ He was already halfway down the ladder. I followed him into the engine room. Water from the high gutter was pouring in. Franz peered behind the bulkhead where he kept his fuse boards; there were little streams running down inside the hull. ‘Scheiße!’ But it was OK-somehow they all missed the wiring. Up on deck we placed rolled up cloths to steer the water into the scuppers.”

Also odd, but only vaguely related to the book are passages like this: “Throughout his life, Blake returned again and again to the figure of Job. In his twenties, he produced several ink sketches of him, an engraving a few years later, a tempera painting and then two sets of watercolours.” p. 231.

This is an English book, and not American focused. That’s fine. The focus is on the UK and Europe which provides an interesting change from the often dumbed down American version of science. Ultimately, Marsden takes an overarching review of how mineral extraction has affected us as humans over the world. He tries in an over short ending to tie things up with a brief discussion on soil, but it is too brief to tie things together. Still, a good effort with some excellent reporting on how the mining process affected the locals. 4 stars

[Saima Baig · Rating 4 out of 5]

Interesting book of the week on BBC Radio 4. Fascinating to know about all the minerals. Might get the book to read it through.

[Farah Mendlesohn · Rating 5 out of 5]

Just my kind of book. Uses a specific topic to drift widely over The State of Things. I learned a great deal (not least that 7Up used to contain lithium to boost your mood.

[Donna Holland · Rating 4 out of 5]

A rich exploration of the minerals underground,From the history of metals and how it has affected our relationship with the planet.

[Kimilo · Rating 2 out of 5]

This was a wild ramble, struggled to see the structure of it. Some interesting facts and stories in between, but missed the overarching setting.

[Rob Thompson · Rating 4 out of 5]

A Journey Through Minerals, Greed and Wonder

Philip Marsden's "Under a Metal Sky" offers readers a mesmerizing exploration of humanity's complex relationship with the mineral world. This work seamlessly blends travelogue, historical investigation, and philosophical inquiry to create a multifaceted narrative that reveals how our pursuit of metals has shaped civilizations and psyches alike.

Marsden's prose shines brightest when he connects geological phenomena to human experience. His descriptions of ancient mining sites transform what could be mere technical exposition into evocative passages that conjure both the physical toil and spiritual significance of extraction. The narrative traverses continents and centuries with remarkable fluidity, drawing unexpected connections between disparate cultures united by their hunger for what lies beneath the earth.

Where the book occasionally falters is in its ambitious scope. Certain historical tangents, while fascinating, momentarily derail the narrative momentum. However, these diversions ultimately contribute to the work's rich tapestry, reinforcing Marsden's central thesis about the universal and timeless nature of our relationship with minerals.

Most compelling is Marsden's examination of how extraction industries have simultaneously driven innovation and exploitation. He refuses simplistic moral judgments, instead presenting the full complexity of how metals have both elevated and corrupted human societies. The "wonder" promised in the subtitle manifests not only in descriptions of mineral formations but in Marsden's capacity to find profound meaning in material that another writer might render dry or technical.
"Under a Metal Sky" ultimately succeeds as both intellectual journey and literary achievement, earning its place among the great works of narrative non-fiction exploring humanity's relationship with the natural world.

[Sorrento · Rating 3 out of 5]

Philip Marsden relates a lot of v interesting facts on his journey to discover more about man's use of mineral which I enjoyed, however I did find his narrative disjointed and difficult to follow the relevance of the pages devoted to Goethe, Blake, Rudolf II etc.

[Mel · Rating 4 out of 5]

A library book that I was unable to finish. What I read I really enjoyed.

[Jenny · Rating 5 out of 5]

I read this book too fast. Would like to go back…once I started looking up all the places on google maps, it got more & more interesting. Really good writer. Maybe too much literature for me.

[Rosie · Rating 4 out of 5]

Marsden combines travel writing, history and geology into a work that crosses Europe to explore how metals and mining have shaped human activities.

[Zac · Rating 3 out of 5]

3.5