Fossils, geology and minerals. Highly acclaimed international earth science blog with over 850 articles and book reviews.
Michael C Mackiewicz (USA) A familiar mineral with an unfamiliar story Graphite is one of those minerals that most people think they intrinsically know until they actually hold a good specimen in their hands. The word ‘graphite’ brings visions of pencils and grey streaks. However, graphite occupies the centre of … Read More
Michael Mackiewicz (USA) Fluorite has long captivated mineral collectors with its range of colours, sharp cubic crystals, and its magical glow under ultraviolet light. Once sought after for its beauty, it is now a mineral that is essential to modern industry and clean-energy supply chains. Fluorite, also called fluorspar, is … Read More
Michael C Mackiewicz (USA) Minerals have shaped human societies since ancient times, but the idea of ‘critical minerals’ is fairly recent. As explored in earlier articles in this series, the Top Ten critical minerals, lithium, cobalt, nickel, graphite, manganese, the rare‑earth elements, tungsten, vanadium, bismuth and antimony are central to … Read More
Michael Mackiewicz (USA) Gallium is one of those odd minerals that somehow gets people’s attention. Unlike cobalt, lithium or the majority of other critical minerals, you do not find gallium in rich ore bodies that can be mined directly. Instead, it shows up in trace amounts inside common minerals like … Read More
Paul Lyle begins GeoHibernica with a slightly mischievous acknowledgement: the book exists only because the author of GeoBritannica was unable to take on its Irish counterpart himself. It is a revealing admission, and one that immediately invites comparison between the two works. That comparison is instructive, although not always in the ways one might expect.
Michael Mackiewicz (USA) Minerals have shaped human progress for millennia, but the concept of critical minerals is a modern one. As discussed in earlier articles, the Top 10 critical minerals (lithium, cobalt, nickel, graphite, manganese, rare earth elements, tungsten, vanadium, bismuth and antimony) are essential to advanced technologies, global economy, … Read More
Michael Mackiewicz (USA) Minerals have shaped the direction of human civilisation for thousands of years, from early use of copper and gold in tools and ornaments, to the extraction of iron and tin during the Bronze Age. However, the idea of critical minerals is much more recent. As explained in … Read More
Michael C Mackiewicz (USA) This is the first of several articles on the Top 10 critical minerals. ‘Critical minerals’ is a relatively modern term that will be explained in this article. Minerals that shaped civilizations Minerals have played a central role in human development for thousands of years. From the … Read More
Wayne Sukow (USA) Found in situ at the Wolverine #2 Mine in Houghton County, MI is a rare and unique Lake Superior agate. Some of those recovered are infused with varying amounts of massive copper, ranging from flecks visible to the unaided eye to solid stretches of native copper. Some … Read More
Tony Forsyth (Australia) Located over 1,100km west of Sydney in New South Wales, Australia is the city of Broken Hill (Fig. 1). Nicknamed Australia’s “silver city”, with a population of over 20,000 people, it is now a prosperous centre for mining, the arts, tourism and film production. However, my wife … Read More
Mike Viney (USA) Introduction The Front Range of the Colorado Rockies is not a place one would expect to find a residence designed in the style of a European castle. So, for me, it was a delightful surprise to learn about the existence of Cherokee Castle in Sedalia, Colorado (Fig. … Read More
Last week, I published a book review of The Trilobite Collector’s Guide, by Andy Secher, in which I suggested that it was a great choice for a Christmas present for those who like geology. I think the same could be said for this (but it’s not all geology). Once again, it has a coffee table book feel, but once again, it is much, much more.
Marta Pino Larrío (Spain) In July 2023, I travelled with fellow geologists to Băile Herculane, an ancient Romanian town in the Western Carpathians, situated between the Danube and the Serbian border. Our mission was to analyse the site for a new railway tunnel that will replace the existing one. Băile … Read More
Deborah Painter (USA) The famed English explorer of the “New World”, Captain John Smith, led expeditions during the early 1600s to create charts and plan settlements along the east coast of the United States, from what is now Virginia to Maryland and, on a subsequent voyage, New England. Smith’s map … Read More
In many ways, this updated guide is exactly what I want from a GA guide – extensive coverage, well written, and oodles of colourful photos and graphics. I liked and used the previous edition (GA No. 2), and it’s a shame that, for example, the Ordovician site of Stockdale Quarry has disappeared, but it – and no doubt other locations – has been replaced by, what I suspect, are just as good, if not better, sites.
Fiona Henderson and Evelyn Krull (Australia) Biochar has the potential to sequester carbon, improve soil health and increase crop yield. Even its production can be classed as beneficial, as it is a by-product of a process that burns waste materials to produce bio-fuel. However, questions remain. Although biochar offers an … Read More
Liz Porter (Australia) Australia has 14 different major types of soil. Maps showing soil profiles of different areas are very useful for farmers, people planning cities, people who look after natural resources and increasingly … forensic scientists! The foray into the world of crime solving by Australia’s Commonwealth Scientific and … Read More
If you have ever wondered what a penguin’s great, great, great, great, great (and so on, for a very long, long time) grandparent looked like, then this is the book for you. Better still, if you are five to nine years old, it is certainly the one for you.
George Burden (Canada) The rickety taxi bumped and rattled its way southward, into the scenic peaks of the Dominican Republic’s northern cordillera. Frequent washouts from seasonal torrential rains make the going tricky and, at times, even a little perilous. However, we finally arrived at a small community, the site of … Read More
Flavia Faedo (UK) The Thiepval Memorial is situated four miles (almost 6.5km) north of the town of Albert, in northern France, and was built to commemorate British soldiers who have no known grave, yet died here during the Great War of 1914-1918. This memorial rises majestically from the woods and, … Read More
Khursheed Dinshaw (India) Gobustan in Azerbaijan is an interesting site depicting prehistoric rock art. The petroglyphs here vary in age from the Upper Palaeolithic Era to the Middle Ages (Fig. 1). A UNESCO World Heritage Site, more than 6,000 images can be seen here (Figs. 2 to 9). The petroglyphs … Read More
The Cro-Magnons were a population of early modern humans (that is, they were physically indistinguishable from us, today), who lived in Europe between about 40,000 and 10,000 years ago, during the Upper Palaeolithic period. This information comes from Trenton Holliday’s excellent book, which tells the story of these people in the context of recent scientific advances. However, while it does not shy away from complex scientific issues, the book is written with a light, understandable touch.
Allen Fraser (UK) Shetland is a spectacular group of islands with a varied geology, a wonderful landscape and a special flora and fauna, peopled by a culture distinct within the British Isles. Shetland remains one of Britain’s natural treasures.” (J. Laughton Johnston) The islands Shetland sits on the edge of … Read More
Deborah Painter (USA) Tiger’s eye is definitely an unusual semiprecious gem because of a phenomenon called “chatoyancy” seen in only a few minerals and stones. “Chat” is of course the French word for “cat”. The golden bands of polished specimens remind one of a cat’s eye. Chatoyancy refers to the … Read More
Khursheed Dinshaw (India) “Let’s organize a hike to Yana to see its impressive rock formations,” suggested Ramesh V, the wellness consultant at Gamyam Retreat, which is a luxury wellness resort located an hour’s drive from Yana. My interest piqued. The next day, I headed to Yana located in Uttara Kannada … Read More
Deborah Painter (USA) Earlier in the month of September 2022, my friend David and I spent an afternoon with a fellow named Ellery, a long-time member of a rock collecting club we joined a year ago. Ellery allowed me to photograph some of his rock and mineral specimens, including a … Read More
