Amgueddfa Blog: Geology

The dinosaur skeleton we know and love as Dippy, has an interesting history. But we know these fossils were first called Diplodocus, right? Well, no probably not….

We’ve heard about how ‘Dippy’ came to London in 1905 – a plaster cast of the original fossil bones kept in the Carnegie Museum Pittsburgh. And thanks to palaeontologists, we can picture it as a living animal browsing in Jurassic forests 145-150 million years ago – seeing off predators with its whip-like tail.

But what about the middle of the story? Where did these fossils come from?

AC-NMW

In 1898 thanks to the steel industry, Andrew Carnegie was one of the richest people in the world. He was busy giving away money for libraries and museums. Hearing about the discovery of huge dinosaurs in the American West he said something like ‘Get us one of those!’, sending a Carnegie Museum team to find a “most colossal animal”.

So, in 1899 in the last days of the American Old West, a Diplodocus skeleton was discovered at Sheep Creek, Albany County on the plains of Wyoming, USA. It happened to be the 4th of July, Independence Day, which prompted the Carnegie team to give the fossil its first nickname - ‘The Star Spangled Dinosaur’. Predictably though, this new species was later published as Diplodocus carnegii.

The dig site would have looked very similar to this one at the nearby Bone Cabin Quarry one year earlier.

To set the scene, these late 1800's photographs are from other parts of Albany County, Wyoming (via Wikimedia Commons).

Dippy’s first name, “Unkche ghila”.

But what about the original people of the plains, the Native Americans? Wouldn’t they have found dinosaur fossils before the European settlers? In her book “Fossil Legends of the First Americans” Adrienne Mayor shows that indeed they did. They visualised the fossils’ original forms as Giant Lizards, Thunder Birds, and Water Monsters, and several of the famous dinosaur collectors had Native American guides. This book shows that Native American ideas about fossils were perceptive of the geological processes involved such as extinction, volcanoes, and sea level change.

( “Clear”, Lakota people, 1900. Heyn & Matzen

The original people of the plains where Diplodocus fossils are found are the Lakota Sioux. James LaPointe of the Lakota people was born in 1893, and recalls a legend he heard as a boy:

“The Sioux called these creatures “Unkche ghila”, roughly comparable to dinosaurs; these oddly shaped animals moved across the land in great numbers and then disappeared. The massive bones of these now extinct creatures can be found in the badlands south and east of the Black Hills. It is not clear when the unkche ghila went extinct, but Sioux geology maintains they were still around when the Black Hills rose from the earth.” From James R. Walker , 1983. ‘Lakota Myth’.

So, via Adrienne Mayor, I’ll give the last word here to the US National Park Service:

“The stories and legends told by American Indians offer a unique perspective into the traditional spiritual significance of fossils and offer an exceptional opportunity to illustrate the interconnectedness of humans and nature.” Jason Kenworthy and Vincent Santucci, “A Preliminary Inventory of National Park Service Paleontological Resources in Cultural Resource Contexts.”

2019 is the 150th anniversary of the Periodic Table of Chemical Elements (see UNESCO https://www.iypt2019.org/). The "International Year of the Periodic Table of Chemical Elements (IYPT2019)" is an opportunity to reflect upon many aspects of the periodic table, including the social and economic impacts of chemical elements.

Sulphur is the fifth most common element (by mass) on Earth and one of the most widely used chemical substances. But sulphur is common beyond Earth: the innermost of the four Galilean moons of the planet Jupiter, Io, has more than 400 active volcanoes which deposit lava so rich in sulphur that its surface is actually yellow.

Alchemy

The sulphate salts of iron, copper and aluminium were referred to as “vitriols”, which occurred in lists of minerals compiled by the Sumerians 4,000 years ago. Sulfuric acid was known as “oil of vitriol”, a term coined by the 8th-century Arabian alchemist Jabir ibn Hayyan. Burning sulphur used to be referred to as “brimstone”, giving rise to the biblical notion that hell apparently smelled of sulphur.

Mineralogy

Sulphur rarely occurs in its pure form but usually as sulphide and sulphate minerals. Elemental sulphur can be found near hot springs, hydrothermal vents and in volcanic regions where it may be mined, but the major industrial source of sulphur is the iron sulphide mineral pyrite. Other important sulphur minerals include cinnabar (mercury sulphide), galena (lead sulphide), sphalerite (zinc sulphide), stibnite (antimony sulphide), gypsum (calcium sulphate), alunite (potassium aluminium sulphate), and barite (barium sulphate). Accordingly, the Mindat (a wonderful database for all things mineral) entry for sulphur is rather extensive: https://www.mindat.org/min-3826.html.

Chemistry

Sulphur is the basic constituent of sulfuric acid, referred as universal chemical, ‘King of Chemicals’ due to the numerous applications as a raw material or processing agent. Sulfuric acid is the most commonly used chemical in the world and used in almost all industries; its multiple industrial uses include the refining of crude oil and as an electrolyte in lead acid batteries. World production of sulfuric acid stands at more than 230 million tonnes per year.

Warfare

Gunpowder, a mixture of sulphur, charcoal and potassium nitrate invented in 9th century China, is the earliest known explosive. Chinese military engineers realised the obvious potential of gunpowder and by 904 CE were hurling lumps of burning gunpowder with catapults during a siege. In chemical warfare, 2,400 years ago, the Spartans used sulphur fumes against enemy soldiers. Sulphur is an important component of mustard gas, used since WWI as an incapacitating agent.

Pharmacy

Sulphur-based compounds have a huge range of therapeutic applications, such as antimicrobial, anti-inflammatory, antiviral, antidiabetic, antimalarial, anticancer and other medicinal agents. Many drugs contain sulphur; early examples include antibacterial sulphonamides, known as “sulfa drugs”. Sulphur is a part of many antibiotics, including the penicillins, cephalosporins and monolactams.

Biology

Sulphur is an essential element for life. Some amino acids (cysteine and methionine; amino acids are the structural components of proteins) and vitamins (biotin and thiamine) are organosulfur compounds. Disulphides (sulphur–sulphur bonds) confer mechanical strength and insolubility of the protein keratin (found in skin, hair, and feathers). Many sulphur compounds have a strong smell: the scent of grapefruit and garlic are due to organosulfur compounds. The gas hydrogen sulphide gives the characteristic odour to rotting eggs.

Farming

Sulphur is one of the essential nutrients for crop growth. Sulphur is important to help with nutrient uptake, chlorophyll production and seed development. Hence, one of the greatest commercial uses of sulfuric acid is for fertilizers. About 60% of pyrite mined for sulphur is used for fertilizer manufacture – you could say that the mineral pyrite literally feeds the world.

Environment

Use of sulphur is not without problems: burning sulphur-containing coal and oil generates sulphur dioxide, which reacts with water in the atmosphere to form sulfuric acid, one of the main causes of acid rain, which acidifies lakes and soil, and causes weathering to buildings and structures. Acid mine drainage, a consequence of pyrite oxidation during mining operations, is a real and large environmental problem, killing much life in many rivers across the world. Recently, the use of a calcareous mudstone rock containing a high proportion of pyrite as backfill for housing estates in the area around Dublin caused damage to many houses when the pyrite oxidised; the case was eventually resolved with the “Pyrite Resolution Act 2013” allocating compensation to house owners.

Conservation of museum specimens

Because iron sulphides are highly reactive minerals, their conservation in museum collections poses significant challenges. Because we care for our collections, which involves constantly improving conservation practice, we are always researching novel ways of protecting vulnerable minerals. Our current project, jointly with University of Oxford, is undertaken by our doctoral research student Kathryn Royce https://www.geog.ox.ac.uk/graduate/research/kroyce.html.

Come and see us!

If all this has wetted your appetite for chemistry and minerals, come and see the sulphur and pyrite specimens we display at National Museum Cardiff https://museum.wales/cardiff/, or learn about mining and related industries at Big Pit National Coal Museum https://museum.wales/bigpit/ and National Slate Museum https://museum.wales/slate/.

Continuing the international year of the periodic table of chemical elements, for September we have chosen carbon, the element which – in coal - has arguably had the most influence on the shaping of the built landscape and culture in Wales.

The Welsh Coalfields

For around 150 years the coal industry has dominated the industrial, political and social history of Wales. Between 1801 and 1911 the population of Wales quadrupled from 587,000 to 2,400,000. This was almost entirely due to the effects of coal mining: either directly through the creation of colliery jobs or through industries reliant on coal as a fuel (eg. steel-making).

There are two major coalfields in Wales, one in the north-east of the country and one in the south.  North Wales produced mostly high volatile, medium to strong caking coal, and the coalfield has a long history of production. By 1913, it was producing around 3,000,000 tons per annum but went into a slow decline afterwards. The last colliery in the area, Point of Ayr, closed in 1996.

The south Wales coalfield is more extensive than that of north Wales.  It forms an elongated syncline basin extending from Pontypool in the east to Ammanford in the west, with a detached portion in Pembrokeshire. The total area covers some 1,000 square miles.

The south Wales coalfield is famous for its variety of coal types, ranging from gas and coking bituminous coals, steam coals, dry steam coals and anthracite. They had a wide range of uses: domestic, steam raising, gas and coke production and the smelting of copper, iron and steel.

Loose jointed and friable roof conditions were more commonplace in south Wales than other UK coalfields which resulted in numerous accidents from falls of roof and sides. The deeper seams are also very ‘fiery’ leading to numerous disasters. Between 1850 and 1920, one third of all mining deaths in the UK occurred in Wales. Between 1890 and 1913 alone there were 27 major UK mining disasters, thirteen of which occurred in south Wales including the 1913 explosion at the Universal Colliery, Senghenydd where 439 men died – the largest loss of life in a UK mining disaster.  North Wales was largely free of major disasters but, in 1934, an explosion at Gresford Colliery killed two hundred and sixty-six men, the third worst disaster in Welsh mining history.

South Wales steam and anthracite coal differ from other coal seams due to the presence of numerous partings (‘slips’) which lie at an angle of about 45 degrees between floor and roof.  This made the coal relatively easy to work as the coal fell in large blocks.  However this large coal was coated with fine dust which was the prime cause of pneumoconiosis, a disease which was more prevalent in south Wales than all other UK coalfields. In 1962, 40.7% of all south Wales miners were suffering from the disease.

A close relationship grew up between coal mining and the local community.  Villages were virtually single occupation communities. In Glamorgan and Monmouthshire half of all adult male workers were directly involved in the coal industry, while in places such as the Rhondda and Maesteg, the proportion could be as high as 75%.

Because of the peculiar geology and geography, south Wales was slow to unionise. However, following the humiliating defeat after the 1898 coal strike, there arose a need for unity and in 1914 the South Wales Federation became the largest single trade union with almost 200,000 members.

From the early 1920s until WW2, the Welsh coalfields suffered a prolonged industrial recession due to the changeover to oil by shipping and the development of foreign coalfields. The numbers of miners fell from 270,000 to 130,000. The industry was nationalised following the war and experienced tremendous changes with the introduction of new techniques and equipment. There was now a greater emphasis on safety, but the coalfields were still dangerous places. In 1960, 45 men died in Six Bells Colliery, 31 died in Cambrian Colliery in 1965 and, perhaps most tragically of all, 144 people died when a tip collapsed on Aberfan, including 116 children.

By the 1980s the threat of mass pit closures arose. In March 1984 the last major strike began and continued for twelve months. Following the defeat of the National Union of Mineworkers, mines began to close on a regular basis. By the mid-1990s, there were more Welsh mining museums than working deep mines.  The last deep mine, Tower Colliery, closed in January 2008. One of the most important influences on Welsh social, industrial and political life has now vanished.

On the 22nd June our new summer exhibition opened. This family friendly exhibition runs until September and delves into the captivating life of snakes, helping you to find out more about these extraordinary and misunderstood creatures. We are hoping to feature more detailed stories about all of the things mentioned below in a series of blogs running through July and August so keep tuning in to find out more.

Dr Rhys Jones at our opening launch event.

Snakes is a touring exhibition created by a company called Blue Tokay with added bonus content generated by our team. Work began on bringing together all of this way back in September 2018 and since then we have been busy researching, writing text and preparing some great specimens for you all to enjoy.

The main exhibition covers all aspects of the lives of snakes, so we focused our efforts on highlighting our collections at the museum. We hold over 3.5 million natural history specimens here, and as you can imagine, not everything is on display. We hold a small collection of 500 reptiles from all over the world. These are mostly preserved in alcohol and stored in jars, but we also have skeletons, skins and eggs. We chose 32 of our best snakes to go out on display. Each of these were carefully rehoused and conserved as many of the specimens were old and in need of work.

Some of the fantastic snake collections at the museum.

Our Conservation intern, Caitlin Jenkins, hard at work rehousing the snakes.

But it’s not just snakes in jars. We have also displayed some fantastic casts of 49 million years old fossil snakes, and 3D printed the vertebra of Titanoboa, the largest snake that ever lived.

Snake evolution case featuring casts of snake fossils.

One of my favourite features of the exhibit are our objects dealing with snake folklore and mythology, featuring a 13th century manuscript showing how snakes were used in medicinal remedies. Also some fantastic ‘snakestones’, actually fossil ammonites with snake heads carved on to the top.

Getting out the Snakestones from the collections.

You may also recognise the statue of Perseus that has long been displayed in our main hall. Perseus is enjoying his new surroundings, with Medusa’s snake ridden head looking positively sinister with the new lighting.

Perseus with the severed head of the serpent haired Medusa.

The exhibition features six live snakes and as I’m sure you can imagine, bringing live animals into a museum requires a LOT of preparation. We have done a great deal of work to ensure that their time with us is spent in 5 star accommodation. Their ‘vivaria’ are purpose built to ensure our snakes are well cared for, including warm and cool spots, as well as a water feature for a bathe. We have a fantastic (and very brave) set of staff who are volunteering their time to looking after them including changing water bowls, and clearing up their poo! Dr Rhys Jones (Cardiff University) has been fantastic with helping throughout this whole process, including coming in every week to feed them. The snakes are all provided by a company called Bugs n Stuff, you can see a video of them installing the live snakes here.

The largest of our live snakes, Prestwick, the Jungle Carpet Python.

Dr Rhys Jones with some of our staff at the live snake care team meeting.

Guy Tansley from Bugs N Stuff with Mela, the Boa constrictor.

Finally, our fantastic learning department, design team and technicians have worked hard to add some fun activities for all to enjoy. Our Spot the Snake pit features, amongst other things, two beautifully conserved models of a cobra and a rattlesnake that date back to 1903, and a real freeze-dried adder! We also have a snake expert quiz, a world map of snakes, and drawing and colouring stations. Volunteers will be in the gallery periodically across the summer with snake handling specimens including a real full length skin of an African Rock Python.

The exhibition runs till 15th September 2019, entry charges do apply, and all your contributions go towards bringing you even bigger and better exhibitions in the future. Please note that there is no live handling of the snakes within the exhibition, there will be a series of bookable handling sessions throughout the summer as well as a Venom themed Open Day in August. To find out more about all of this, go to our What's On page.

 

Into June and we have selected silicon as our element of the month. This element might not be instantly recognisable as of significance to Wales, but it does have an interesting history.

Silicon (chemical symbol – Si), atomic number 14, is a hard but brittle crystalline solid, with a blue-grey metallic lustre. Silicon is the second most abundant element (about 28% by mass) in the Earth’s crust after oxygen with which it has a strong affinity. Consequently, it took until 1823 for a scientist - Jöns Jakob Berzelius – to prepare it in pure form.

In Wales, silicon is present virtually everywhere in one form or another: from quartz (silicon dioxide, SiO2) in sedimentary siltstones, sandstones and conglomerates; complex silicates in igneous and metamorphic rocks; to sediments in soils.

Silica (silicon dioxide, or quartz) was mined extensively in the Pontneddfechan area, in South Wales, from the late 18th century until 1964 for the manufacturing of firebricks for kilns and furnaces. It occurs as a very pure material highly concentrated in quartzite within a geological unit known as the Basal Grit. Weathering and erosion of the quartzite has produced deposits of silica sand and this was extensively quarried for the production of refractory fire bricks for the smelting industries.

In North Wales, a little-known trade in rock crystal – a colourless, glassy variety of quartz crystal – took place in Snowdonia during the 18th and 19th centuries centred upon the village of Beddgelert. T. H. Parry-Williams refers to this in one of his writings. Miners and mountain guides searched for veins of quartz in the mountains and collected crystals to sell to tourists as curios and some were possibly used to make crystal chandeliers. Later, crystals were occasionally discovered in the vast slate quarries, or during the large-scale construction of forestry tracks during the 1960s.

Silicon, as silica (another name for silicon dioxide) is also important to certain organisms. In particular diatoms and sponges.

Diatoms are single-celled microscopic algae with a complex cell wall made of silica. They are abundant in all waters, produce oxygen and are food for other aquatic organisms. Diatoms are also frequently used to monitor water quality.

Sponges build their skeletons from a framework of tiny elements called spicules, which are made of silica in most sponge groups.  One of the most beautiful examples is the Venus’ Flower Basket glass sponge, which lives anchored to the deep ocean floor near the Philippines.  A pair of shrimps lives inside this sponge, breeding inside it and spending their whole lives protected within its delicate glass walls.  Thanks to this unusual symbiotic relationship, the dead skeletons of Venus’ Flower Baskets are a popular wedding gift in Japan.

Sponges are the most primitive kind of animal on Earth, and their resistant spicules are found as fossils from as far back as 580 million years ago. Silica is also important in the preservation of other types of fossil.  When dead animals or plants are buried, silica from groundwater can fill in the pores and other empty spaces in wood, bone or shells, and/or it can replace the original remains as they decay or dissolve.  This is most common in areas where the groundwater has high silica levels, due to volcanic activity or erosion of silica-rich rocks.  The organic remains act as a focal point for silica formation, and often the rock surrounding the fossils is made of different minerals.  For example, shells that were originally made of calcium carbonate can dissolve and be replaced by silica, whilst being fossilised within limestone (calcium carbonate).  Extracting the fossils is a simple process of putting the rock in some acid and waiting for it to dissolve, leaving behind the silicified fossils.  The Museum’s fossil collections include many silicified shells of brachiopods, ammonites, bryozoans and other sea creatures.

One of the most spectacular types of fossil preserved in silica is ‘petrified wood’.  Silica replaced the original cells of the wood as it decayed and also filled in any gaps, literally ‘turning it to stone’.  In some places, including Patagonia and the USA, whole tree trunks replaced by silica are found in so called ‘petrified forests’.  Other plant fossils, such as cones, can also be fossilised in this way.

Chert is a rock made of very small crystals of silica.  Many major chert deposits formed at the bottom of ancient oceans from ‘siliceous ooze’, which is made of the skeletal remains of millions of tiny organisms including diatoms and radiolarians (single-celled plankton).  Chert nodules can also form within other rocks through chemical processes. 

Chert found within chalk is known as flint, and was a very important material for making tools throughout Prehistory. Tools are made by knapping, that is striking a prepared flint edge, or striking platform, with a harder stone to detach pieces called flakes or blades. These flakes, blades, and indeed the core from which they are struck can then be modified with secondary working into fine tool forms. Amongst the most skilful are fine arrowheads, including these from a Bronze Age grave at Breach Farm, Vale of Glamorgan, Wales. Flint was generally the material of choice for making sharp cutting tools as it is so fine-grained and fractures conchoidally and cleanly it gives a really sharp cutting edge. Indeed, so much so, that anecdotally eye-surgeons are reported to occasionally use a freshly struck flint blade in the operating theatre!

Because it is very fine-grained and hard, chert can preserve fossils of very small things from far back in our planet’s history.  The oldest potential fossils on Earth are found in cherts, and include the possible remains of bacteria from over 3 billion years ago.  Younger fossils, from the Rhynie Chert of northern Scotland, provide a glimpse of one of the earliest land communities, 400 million years ago.  Simple plants, and animals including primitive spider-like creatures and scorpions, were preserved in fine detail thanks to silica-rich water from volcanic hot springs.

Opal is a hydrated form of silica, meaning that it contains between 3 and 21% water.  Unlike standard silica, it does not have a set crystal form, but some of its forms diffract light, creating a beautiful iridescent effect in a variety of different colours.  For this reason, opal has been prized for centuries as a gemstone for making pendants, rings and other jewellery.  Australia produces a lot of the world’s opal, and is also a source of rare and spectacular opalised fossils.  The shells of invertebrates such as belemnites (prehistoric squid-like creatures), and even dinosaur bones, have been replaced by opal, creating very colourful specimens in a world where fossils are usually grey or brown.