Category: minerals

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Geology Museum of Ipoh, Malaysia

Khursheed Dinshaw (India) The Geology Museum of Ipoh in Malaysia is located inside the premises of the Department of Minerals and Geoscience Malaysia (Fig. 1). The museum is an interesting venue where you canlearn about both the geology and the geosciences of the country. The easy to navigate museum was established in the year 1957. It is divided into seven galleries, all of whichare located on the ground floor (Figs. 2, 3 and 4). And theynarrate the geology of Earth, emphasising the importance of geology to the human race. Fig 1: Entrance to the geology museum of Ipoh in Malaysia. Fig 2: The different galleries. There is an impressive collection of fossils, minerals and rocks. There is also a gallery showcasing samples of tin ore (Cassiterite), which have been collected from the various tin fields of the country. Fig 3: One of the seven galleries. Fig 4: All the galleries are located on the ground floor. I particularly liked the amber exhibit (Fig. 5), which is part of the largest piece of amber ever found in the world. Its age dates to Miocene to about 20 million years ago.The original piece was excavated from a coal mine in the Kapit Division of the state of Sarawak in Malaysia. Embedded in coal,it weighed 70kg and was divided into three sections, with each section being almost equal in size. While the amber piece in the Geology Museum of Ipoh continues to attract and educate visitors, the other two pieces can be viewed … Read More

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Celebrating the Ashdon Meteorite

Michael E Howgate One hundred years ago, a grapefruit-sized lump of rock ended its four and a half billion year long journey through space by crashing into a field in northwest Essex. To be more precise, at 1pm on Friday, 9 March 1923, Frederick Pratt, a thatcher and farm labourer, heard what he described as a loud “sissing” noise, and a couple of seconds later saw: a projectile fell about ten or fifteen yards from him, causing the earth to spout up like water” (News report in The Times newspaper, 7 June 1923). Three days later and suitably equipped, he went back to the spot with a friend and they dug up the ‘Ashdon’ meteorite. Being a sensible chap, he knocked a piece off, presumably to check that it was not just a common flint he had unearthed, and then took it to the local police station. The Saffron Walden bobbies were not interested, so he took it home to Wendens Ambo. Here, he showed it to his vicar, the Reverend Francis W Berry who, being an alumnus of Trinity College Cambridge, showed much more interest. Berry recognised the importance of Pratt’s find and purchased it from him, so that he could donate it to the Mineralogical Department of the British Museum (Natural History). The keeper of mineralogy, Dr. George T Prior, a noted expert on meteorites visited the site three months later with both Frederick Pratt and the Rev. Berry in attendance. (Prior’s description of the Ashdon meteorite appeared … Read More

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The how and why of Tiger’s eye

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 way the distinctive bands of yellow and golden brown within the polished stone refract light as one tilts and moves the stone. It seems to possess an inner dimension. That inner dimensionality effect is due to the fibres of crocidolite asbestos (a variety of magnesio-riebeckite) locked within the stone (Fig. 1). Magnesio-riebeckite is composed of silicon, iron and sodium. Quartz is composed of silicon and oxygen. Quartz has impregnated the greater portion of crocidolite within Tiger’s eye and only a small percentage is crocidolite asbestos. This is why Tiger’s eye is known as one of the “pseudomorphs”, which is a mineral that transforms partly into a different mineral. Fig. 1. This specimen of crocidolite from the Mineralogical Museum in Bonn resembles a shimmering holiday decoration. Its beauty is in sharp contrast to its reputation as asbestos, which is listed as most hazardous to health. (Credits: Raimond Spekking.) A hydrothermal metamorphic process created the pseudomorph known as Tiger’s eye. In a hydrothermal condition during metamorphism of the bedrock in which crocidolite occurs, the mineral will experience tiny fractures. Quartz grows on the outer surface of the crocidolite. This process repeats itself until the crocidolite is surrounded completely in quartz and imbedded … Read More

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Geopedia: A Brief Compendium of Geologic curiosities, by Marcia Bjornerud (with illustrations by Haley Hagerman)

This is a charming little book, which describes itself as an “admittedly idiosyncratic compendium of [geological] words and phrases chosen because they are portals into larger stories”. It succeeds brilliantly at its professed goal, combining a great deal of information, education, and a gentle sense of fun, brought out very nicely by some attractive and humorous illustrations.

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A splendid falsification: a double story

Raymond Dedeyne and Rik Dillen (Belgium) This is a story in two parts about two fake mineral specimens of a double salt, written by two authors with the same initials… You can find fake mineral specimens all the time at mineral shows, but also on location. A good example is Morocco, where unbelievable quantities of fake amethyst and other geodes are sold along the roadside. Any collector, who knows something about minerals, will easily recognise such fakes and may, on somewhat closer inspection, discover lots of glue, even with the naked eye. Two years ago in Gent, the first of our two authors (Raymond) bought, at a show, an attractive specimen consisting of several, very well-formed crystals (up to 2.5cm wide) on a matrix of gypsum crystals. At first sight, the crystals looked black, but, on closer examination, they appeared deep red-violet because octahedrical crystals of this sort are “penetration-twins” (crystals that have the appearance of passing through each other in a symmetrical manner). The seller claimed that the locality where it was “found” was Rudna in Poland. It is difficult to blame the man too much, as he told Raymond from the beginning that the crystals were man-made. He explained that he had found the piece himself in a Polish salt-mine that, after exploitation, had been filled with liquid waste from an alum mine. Therefore, the crystals would have been formed by the evaporation of water, which lead him to label the specimen as “alum”, based on the origin … Read More

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Meteorites: ‘rocks’ from space

Dr Vic Pearson (UK) Every year, thousands of tonnes of dust and rock penetrate the Earth’s atmosphere. The fiery passage of these objects produces the familiar ‘shooting star’ phenomenon, known as meteors. Much is destroyed during this descent, but some material is delivered to the Earth’s surface, either as meteorites or micrometeorites (the latter being typically less than 1mm). However, only 1% of the surviving material is large enough for identification and recovery, making meteorites and micrometeorites much sought after, both scientifically and commercially. Fig. 1. Meteors, or shooting stars, are a regular sight in our skies. Not all survive atmospheric entry but produce spectacular fireballs. (Image courtesy of A. Danielson.) Naturally, bombardment by extraterrestrial materials has been ongoing throughout Earth’s history. The early Solar System would have been a turbulent time and the young Earth was subject to much greater amounts of extraterrestrial infall than today. Our geological record contains many impact craters, and fossilised meteorites have been found in Ordovician sediments in Sweden (Schmitz et al., 2001), thought to be the result of the catastrophic break-up of an asteroid 470 million years ago. Today, it is accepted that the majority of meteorites are fragments of asteroids broken off during collisions with other extraterrestrial objects, perturbed from their orbits by the gravitational effects of Jupiter. The origins of micrometeorites are less well constrained and evidence abounds for both cometary and asteroidal origins. Types of meteorites Meteorites are generally classified as either falls or finds. Falls are those that are … Read More

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Geology museums of Britain: Kendal Museum of Natural History and Archaeology, Cumbria

Jon Trevelyan (UK) Kendal Museum is one of those charming, cluttered museums I feared were dying out (Fig. 1), but still seem to defy the odds and continuing surprising visitors. Like the museum in Whitby (see Geology museums of Britain: Whitby Museum, Yorkshire), at Kendal, there seems to be exhibits stuffed anywhere possible, with surprises everywhere you look. The museum itself is a local museum in Cumbria, on the edge of the Lake District in northwest England. It was founded in 1796 and includes collections of local archaeology, history, geology and natural history from around the globe, but especially from the Lake District itself. Fig. 1. A model boat and bicycle – typical of the eclectic displays. In April 2011, Kendal Museum achieved the Visitor Attraction Quality Assurance Scheme assessment, awarded by Visit England. It is managed by Kendal College on behalf of South Lakeland District Council and is part of the Arts and Media campus at the North End of Kendal. History The Museum of Natural History and Archaeology is one of the oldest museums in the UK, with displays of local and global natural history, and archaeology. Kendal’s first museum was founded in 1796 by William Todhunter, who exhibited a collection of fossils, minerals, plants, animals and antiques. In 1835, the Kendal Literary and Scientific Society took over the museum and, as the collection grew, the museum had to be rehoused several times. In 1913, the current building was offered to the Town Council to house the museum. … Read More

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Oxygen-free storage for pyrite speciments

Dr Caroline Buttler (UK) Oxygen is responsible for the majority of chemical reactions that lead to the decay and degradation of museum specimens; the corrosion of iron and the fading of many pigments when exposed to ultraviolet light could not occur without the presence of oxygen. It is also essential for the life forms responsible for biological decay such as insects, fungi and bacteria. The most common oxidation reaction affecting geological specimens is pyrite decay, which damages specimens containing pyrite or marcasite.  Pyrite decay occurs when the sulphide component in these minerals oxidises to form ferrous sulphate and sulphur dioxide, and can result in the complete destruction of the specimen and the associated labels and packaging materials. If pyrite specimens can be stored without oxygen then deterioration could be prevented. Fig. 1. Ammonite specimen with pyrite decay (©National Museum of Wales). The technology to produce oxygen-free environments to museum standards has burgeoned in the last few years. Nitrogen and other inert gases such as argon and helium have been successfully used to display specimens without oxygen, but it is costly and only used for rare or valuable objects. For example the American Charters of Freedom, which include the Declaration of Independence, the Constitution and the Bill of Rights, in the Rotunda of the National Archives Building in Washington, DC, are displayed in cases inside which an anoxic environment has been created containing a humidified argon atmosphere at 19°C. Anoxic storage can also now be achieved relatively cheaply and efficiently with … Read More

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Book review: Essex Rock – Geology beneath the Landscape by Ian Mercer and Ros Mercer

To be fair, Essex has never been famed or well-regarded for its geology, at least not by me. I know it has its locations – Walton-on-the-Naze springs to mind – but not a lot else. However, this guide is set to change all that. Full colour photographs and illustrations (on virtually every page), with 416 pages of excellent text, with particularly good sections on the London Clay and Red Crag, it is as good as it gets. It is worth owning for its own sake, even if you are not going to, or are living in, Essex.

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Geology museums of Britain: The Hunterian, Glasgow

Jon Trevelyan (UK) This is the second of my articles on the geology museums of Glasgow (see also Geology museums of Britain: Kelvingrove Art Gallery and Museum, Glasgow). The Hunterian contains for some Scotland’s finest collections, covering subjects such as Roman artefacts from the Antonine Wall (fascinating, given that its big, southern, brother – Hadrian’s Wall – gets all the attention), and scientific instruments used by eminent Scottish scientists, James Watt, Joseph Lister and Lord Kelvin. In fact, the Hunterian’s whole collection is ‘Recognised’ as nationally significant in Scotland. It is also home to one of the most distinguished public art collections in Scotland. However, as always, it was the geology and palaeontology that I went to visit (Fig. 1). Fig. 1. The hall of the museum, with the geology and palaeontology exhibits set out below. The Hunterian’s founding collection came through the bequest of the eponymous Dr William Hunter (1718-1783). The museum itself opened in 1807, and a catalogue was published in 1813 (Fig. 2) by Captain John Laskey, who took visitors through the museum room by room and case by case, describing the items on display. Fig. 2. The catalogue of the original museum contents, by Captain John Laskey, with a lovely shark’s tooth from the original collection. And, apparently, the fossil collections are among the largest in the UK and were built up over the last 200 years from departmental research and teaching collections. Fig. 3. Ripple marks covered in trace fossils. Fig. 4. Copious fossils on … Read More

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Geology museums of Britain: Kelvingrove Art Gallery and Museum, Glasgow

Jon Trevelyan (UK) When I went up to Glasgow to attend my son’s graduation, I deliberately made some time to visit Kelvingrove Art Gallery and Museum to explore its 22 galleries. These cover everything from art to animals, Ancient Egypt to Charles Rennie Mackintosh and much, much more besides. However, the reason why I am including Kelvingrove in my series covering the geology museums of Britain, and the real reason for my visit, is its gorgeous collection of fossils, in particular, significant ones found from Scotland and, indeed, in and around Glasgow. Located in the beautiful Kelvingrove Park (Fig. 1), the art gallery and museum opened in 1901 and is clearly a firm favourite with local people and visitors. It has stunning architecture (Fig. 2) and a family friendly atmosphere; and has relatively recently been redesigned – without losing its Victorian traditions and ideals – so that it is upgraded for the twenty-first century. Fig. 1. The museum is located in Kelvingrove Park, which necessitates a lovely walk through the grounds of this Victorian, public park. Fig. 2. The magnificent frontage of Kelvingrove Art Gallery and Museum. In fact, Kelvingrove started life as typical Victorian museum (Fig. 3), founded by (as the guide puts it): … the wealthy classes to assert their cultural worth and improve the people of the city”. Fig. 3. The roof of the Victorian entrance hall. However, as I say, there have been improvements, which were achieved by asking Glasgow residents what they approved of the … Read More

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Geology museums of Britain: Yorkshire Natural History Museum, Sheffield

Jon Trevelyan (UK) Fig. 1. The museum’s logo. To no little fanfare, this new museum of natural history (and, in particular, fossils) opened on 13 August 2022. James Hogg, who is Chairman at the Yorkshire Natural History Museum (Fig. 2), only had the idea for it earlier this year. Fig. 2. The museum from the outside. James (Fig. 3) true passion for palaeontology came when he was a student. His background is one an economist (in particular, the economic history of institutions and economic growth). However, his idea for the museum is based on his interest in growing a public institution so as many can benefit as possible in the long-run. Fig. 3. James Hogg, with the skull of a huge ichthyosaur. After the idea of the museum took shape, James quickly renovated what was a badly dilapidated property (Figs. 4 and 5) to make it happen. Fig. 4. The inside of the building earlier this year. Fig. 5. The refurbishments have had to be extensive. Now finished, the museum’s exhibits include fossils that have been found along the Yorkshire coast from the Jurassic period, from ammonites to belemnites to those huge behemoths, such as ichthyosaurs, that once hunted in the Jurassic oceans. However, not only is the museum a store for natural history specimens, it will also actively research the collection and will provide visiting academics free access to it. That is, the stated purpose of the museum is to create a dedicated natural history museum in the north … Read More

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The violent story of Cumbria’s ancient volcanoes

Ian Francis and Bruce Yardley (UK) The violent eruption that occurred near the Pacific island of Tonga in January 2022 reminded the world of the ferocious power of volcanoes. The most destructive eruptions can bury huge areas in layers of ash and lava, generate tsunamis, and even alter the Earth’s climate by injecting vast quantities of ash and aerosol droplets high into the atmosphere. Modern Britain is luckily far from any active volcanoes (Vesuvius in Italy, and the volcanoes of Iceland are the nearest to us), but this was not always the case: geological evidence shows that around 455 million years ago, during the Ordovician Period,an intense, but short-lived, periodof volcanic activity took place inwhat is now the Lake District. The geological record of that activity is mainly found in Lakeland’s high and rugged central fells, stretching from Ennerdale and Wasdale in the west, across to Haweswater in the east. Most of the Lake District’s highest fells are found in this central belt, including the Coniston fells, Pillar, Great Gable, Kirk Fell, the Sca Fells, Esk Pike, Crinkle Crags, the Langdales, Helvellyn and High Street (Fig. 1). Fig. 1. Volcanic rocks form the high central fells of the Lake District. The image shows banded volcanic ash beds (tuffs) on the flank of Glaramara, looking east over Heron Crag (in shadow), Ullscarf, and beyond the Helvellyn range. (Photo: Stuart Holmes.) As far back as the early nineteenth century, those familiar with the rocks and landscape of the Lake District (such as … Read More

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The mud volcanoes of Azerbaijan

Khursheed Dinshaw (India) The first time I saw a mud volcano at close range was in Rotorua in New Zealand. I was fascinated – the raw energy of the erupting mud massively appealed to me. Once back home, I read up on mud volcanoes and learnt that, out of the almost 700 present in the world, about 300 of which are located in Azerbaijan and the Caspian Sea. No wonder scientists call Azerbaijan ‘the region of mud volcanoes (Fig. 1). These mud volcanoes reach heights of 200 to 500m and temperatures of 1,000 to 1,2000C. They include active and extinct underwater, island-type and oil producing volcanoes. In Azerbaijan, one can find these natural wonders on the Absheron Peninsula, at Gobustan and the Shirvan plain. Fig. 1. A map of the mud volcanoes of Azerbaijan (© Mark Tingay and Google Earth). Recently, I was fortunate enough to visit the country and booked a tour to Gobustan to experience the famed mud volcanoes, which are locally known as ‘Pilpila’ (Fig. 2). One can drive up to the designated spot in any vehicle, but the last few kilometres necessary to reach the volcanoes is only possible by authorised cars driven by locals who know the landscape like the back of their hand. This is important, because the terrain is barren and there are no marked roads, routes or signposts to get to the mud volcanoes. Fig. 2. Mud volcanoes are called Pilpila in Ajerbaijan. My driver was born and brought up in a … Read More

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Stones that illustrate themselves

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 rough piece of ‘wonderstone’ of approximately 30cm in length and 19cm in width, from southern Utah, USA (Fig. 1). Fig. 1. Shinarump Wonderstone is a variety of chalcedony that features swirls and other decorative patterns. (Credits: Deborah Painter; specimen from the collection of Ellery Borow.) The piece contained what looked like a painting of the flanks of a slot canyon one might see in the very area where it is found (Fig. 2). Fig. 2. A slot canyon in Page, Arizona USA, just 180km to 185km from known sources of Shinarump Wonderstone. It reminds one of the ripples and swirls in the Wonderstone in Fig. 1. (Credits: Brigitte Werner, Pixabay.) On the opposite side of the same specimen was a fish’s head, complete with an ‘eye’ (Fig. 3). Fig. 3. This ‘fish head’, complete with a fishy ‘eye’ is the image that greets you when you turn over the Shinarump Wonderstone specimen in Fig. 1. (Credits: Deborah Painter; specimen from the collection of Ellery Borow.) None of the images were artificial or cut in a particular way to bring out these ‘images’. I was instantly reminded of the pietra paesina stones of the Florence area of Italy. The latter have … Read More

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Drought in South Australia creates soil problems

Dr Paul Shand (Australia) In South Australia, the staff of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Land and Water have recently shown that the River Murray, adjacent wetlands and the Lower Lakes (Alexandrina and Albert) close to the Murray Mouth are being seriously impacted by a combination of low water levels and the presence of acid sulfate soils (ASS). The Lower Lakes and the floodplains below lock 1 at Blanchetown are undergoing their first drought since the introduction of barrages more than 50 years ago. Lakes, such as Lake Bonney and Lake Yatco, as well as several wetlands formed by the River Murray, are being isolated as one option to generate water savings and help mitigate drought-related problems in the Murray-Darling Basin. Field observations and chemical analysis confirm the occurrence of both sulphuric materials (pH <4) and sulphidic materials (high sulphide concentrations and pH >4) in a range of ASS subtypes (Fig. 1). Fig. 1. Acid Sulphate Soil with sulfuric material near Swanport adjacent to the Murray River. In addition, some areas contain ‘monosulphidic black ooze’, that causes rapid oxygen depletion of lake and drainage waters when the ooze is mixed with oxygenated waters during disturbance (Fig. 2). Fig. 2. extensive cracking and accumulation of white and yellow Na-Mg-Fe-Al-sulphate-rich minerals or salt efflorescences. Unpleasant smells (‘rotten eggs’), as a result of rotting vegetable matter and the release of gases, have been experienced in these areas of exposed soils when water levels are extremely low or the lakes have … Read More

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Geology Museums of Britain: Portland Museum, Dorset

Jon Trevelyan(UK) Fig. 1. A huge Titanites giganteus adorns the doorway. I visited this little museum a while ago while on a Geologists’ Association field trip. I have passed it several time and always loved the large Titanites giganteus above the door (Fig. 1) of this picturesque cottage (Fig. 2). As a result, I had always wanted to visit, but more particularly I want to see the famous fossil turtle (Fig. 3) that is exhibited there. Fig. 2. One of the two seventeenth century cottages making up the museum. Fig. 3. The lovely fossil turtle at the museum. In fact, Portland Museum is a lovely example of a local museum containing (among other things, geology (Fig. 4), in this case, tucked away in a beautiful part of the ‘island’ in two seventeenth century cottages, near Rufus Castle and the popular Church Ope Cove. Fig. 4. Some of the geological exhibits at the museum. The Isle of Portland in Dorset represents the most southerly point of the Jurassic, which is a UNESCO designated World Heritage Site and famous for its geology, fossils and geomorphology. It is joined to the mainland by the equally famous Chesil Beach but has always been regarded (not least by its inhabitants)as separate from the mainland, and this is reflected in the museum’s collection. That is, Portland Museum does not just contain geology and palaeontology; its exhibits also reflect the Isle’s history and people. Portland Museum was founded in 1930 by Dr Marie Stopes, renowned for her … Read More

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A new Park County gem discovery: Tarryall fire agate

By Steven Wade Veatch Exceptional specimens of iridescent fire agate have recently been found in Park County in the USA, close to Tarryall Creek and near the Tarryall Reservoir. Fire agate is a variety of chalcedony (pronounced kal SED’ uh nee), a form of microcrystalline or cryptocrystalline (crystals too small to be seen without high magnification) quartz (SiO2). It contains inclusions of iron oxide (limonite) that produce an iridescent effect or ‘fire’. Chalcedony is generally formed near the surface of the Earth, where temperatures and pressures are low. The Tarryall fire agate has a botryoidal (grape-like) growth form. The agate is also layered: it contains thin layers of plate-like crystals of iron oxide in various planes. When light travels through these thin layers, the planes produce the iridescent colour play of red, gold and green. Fig. 1. Good fire agates are impressive in their rich and dramatic colour play. They form in cavities and cracks in the country rock from low temperature, silica-rich waters, in a way similar to how black opal forms. Lee Magginetti specimen. Photo date June, 2007, © by S. W. Veatch. The fire agate specimens were found as seams in granite near the Tarryall Creek. This  is a tributary of the South Platte River, approximately 25 miles (40km) long, in Park County, central Colorado. It drains a portion of north and central South Park, an intermontane grassland south-west of Denver. Tarryall Creek runs in several forks along the continental divide in the Pike National Forest and … Read More

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That Arizona hot spot might be a volcanic field

Deborah Painter Let’s see, when I say “Arizona hot spots”, what might come to mind for many people are the restaurants, nightclubs and sports events in Phoenix (the US state’s largest city), the Grand Canyon of the Colorado River, attracting visitors from around the world, Tombstone (the infamous “town too tough to die”, where the equally infamous 1881 gunfight at the OK Corral took place), and any portion of the desert in the daytime during August. But how many people think of the many volcanoes in Arizona USA, part of a volcanic field that is likely not finished erupting? Arizona, USA has seven young (Quaternary Period) volcanic fields. The three youngest fields are the San Francisco, Uinkaret and Pinacate volcanic fields. The first two of these young fields are on the Colorado Plateau of northern Arizona; the Pinacate Field is much farther south on the Arizona-Mexico border. The San Francisco Field is the focus of this article. It is situated near Flagstaff and Williams in northern Arizona (Fig. 1). It extends approximately 5,0002km from Williams to the Little Colorado River. There are slightly over 600 cones. The field was active as recently as 932 BP (Before Present), with the eruption that formed Sunset Crater at Sunset Crater Volcano National Monument. Fig. 1. The San Francisco Volcanic Field. (Credits: United States Geological Survey/Wikimedia Commons.) The spectacular San Francisco Peaks within this field are originally a single stratovolcano that experienced deep erosion (Fig. 2). Mount Elden near Flagstaff is a large volcanic … Read More

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German Miners in Cumbria

By Jean Tyler One fine Summer’s day in 1564, a group of men on horseback made their way westward from Carlisle along the rough road to Keswick. One of their number rode with the covered wagon that contained clothing, personal chattels and the tools of their trade – mining. These men came from Germany and were the finest miners and smelters in the world. They were here in England at the request of the English Crown and their job was to extract the rich, glowing copper from the mineral veins of Lakeland. So begins the story of mining in this country. The first group of ten men arrived in Keswick in 1564 and were easily accommodated in local lodgings. What a flurry of excitement this must have caused in this little town that consisted of no more than one muddy street with a few squalid yards running off it. At that time, the housing was of timber and wattle daub construction with bracken-thatched roofing. Behind the houses ran strips of land with middens, pigsties and more very basic housing – buildings that were little more than hovels. The arrival of the Germans created a flutter amongst the local girls who were soon vying with each other for the attention of these small, tough men from overseas. Unhappily, some of the inhabitants were suspicious of the foreign strangers who were set to earn good money doing a proper job and violent confrontation eventually resulted in one of the incomers, Leonard Stoulz, … Read More

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Building stones of the Ancient World

By Ken Brooks (UK) Local stone was an essential element in the development of early civilisations, as its availability and quality determined the building styles that they created. The effective working and use of stone as a building material was a skill acquired by man at an early stage of history in many different regions of the world. Today, we can identify their methods of working stone by studying the buildings, quarries and the tools that have survived them. Egypt For thousands of years, the River Nile has carved its way through areas of sandstone, granite and limestone on its 750-mile journey through Egypt to the Mediterranean. From very early times, and even to the present day, the Egyptians have built their homes with bricks made from mud – an abundant raw material along the banks of the River Nile. It was around 5,000 years ago, as organised religion became established, that they began to use locally available stone to construct temples and pyramids. Between 2590BC and 2500BC, the ancient Egyptians built three huge pyramids on the Giza plateau (near present-day Cairo). Fig. 1. The pyramids at Giza. The bedrock in this area is a nummulitic limestone dating from the Eocene period, 34 to 55mya. It is an interesting thought that some of the largest man-made structures on earth were constructed from the fossil remains of tiny organisms (foraminifera). Work on a pyramid began with the extraction of limestone blocks at a nearby quarry. The only tools the Egyptians had … Read More

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Lake District: Landscape and Geology, by Ian Francis, Stuart Holmes and Bruce Yardley

I recently reviewed another of the guides in Crowood Press’s excellent “Landscape and Geology” guides, which was undoubtedly a great read. And this one is equally good, with great, full colour pictures, maps and diagrams, and easy to read text, with descriptions of interesting walks and what can be seen on them.That is, there are easy-to-understand explanations of how the rocks formed and how the geology affects the landscape, and there is also an n exploration of the long human story of the landscapes.

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Iceland: Classic Geology in Europe (3rd edition), by Thor Thordarson and Ármann Höskuldsson

reviewed the 2nd edition of this guide a while ago and, as I said then, Iceland seems to set the hearts of certain geologists racing and, reading this field guide and that previous incarnation, it is abundantly clear why. Iceland’s fascinating geology is clearly set out in this concise and authoritative book. The island, astride the Mid-Atlantic Ridge, is a ‘natural laboratory’ where the earth sciences can be watched in real-time. Rifting of the crust, volcanic eruptions and glacial activity are among a host of processes and features that can be observed in this fascinating land.

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Book review: Isle of Wight: Landscape and Geology, by John Downes

This is another guide in the excellent “Landscape and Geology” series of local geological guides published by The Crowood Press. And this is as good as the others. Admittedly, it has a wonderful subject matter, because the Isle of Wight is a geological gem with its 110km long coastline displaying a range of rocks dating from Lower Cretaceous to Oligocene age. I know from personal experience that many of its sands and clays contain collectable fossil bivalves and gastropods, and its famous dinosaur footprints attract attention from both geologists and tourists, with always the possibility of finding a bone or two.

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Meteorites: A primer

Dr Kendal Martyn Meteorites have long held fascination for me – that is, they aren’t from this planet. Added “glamour” has come from recent suggestions that at least one meteorite impact on earth could be responsible for mass-extinction events, the largest “smoking gun” in evolutionary selection. Also, meteorites are the … Read More

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Book review: Minerals of the English Midlands, by Roy E Starkey

Goodness me! This is a massive work (432 pages) – but written with enthusiasm from the heart, with authoritative text, lovely photos throughout, fascinating anecdotes and history, with detailed geological descriptions of all the relevant counties. Now, I’m no expert on minerals, which fall well outside the scope of my interests. However, I cannot praise this book too much.

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Book review: Introducing Geophysics, by Peter Styles

Notwithstanding the somewhat daunting use of the word “geophysics” in the title, this is another great book in Dunedin’s Introducing Earth and Environmental Sciences series of guides. In fact, In fact, the only real way to understand the Earth, in all its large and slow-moving immensity, is to study its physics and that means using the classical disciplines of heat, gravity, magnetism, electricity, vibrations and waves. That is, everything we know about the deep Earth has been learnt from geophysics.