The oldest objects in the Museum's collections are 4,500 million year-old meteorites from space. However, the oldest objects from Wales are rock specimens from the Old Radnor district, Powys, which formed about 700 million years ago, when Wales as we know it today had yet to take shape.

Molten rock from Avalonia

These rocks form the three small distinctive conical hills of Hanter, Stanner and Worsel Wood, and are composed of gabbro, dolerite, and granite — igneous rocks that were once molten. When these formed, around 700 million years ago, Wales lay deep in the southern hemisphere. Along with England and parts of Newfoundland, New Brunswick and New England it formed part of the mico-continent Avalonia, which lay on the margin of the vast continent of Gondwana.

At this time Scotland was close to the equator, attached to the North American continent of Laurentia, and it was hundreds of millions of years later that it separated and merged with southern Britain.

Very old rocks are also found in Anglesey and the Lleyn Peninsula, and similar rocks probably underlie the whole of Wales. Typically we only see these ancient rocks where they have been brought to the surface by upward movement along major fault zones.

How do we know that these are the oldest rocks in Wales?

These rocks contain no fossils. So how do we know that those from the Old Radnor district are the oldest, and what age they are? The answer lies in the minerals from which a rock is made, and the chemical elements that these minerals contain.

Radioactive decay

Rocks are aggregates of minerals, which in turn are composed of chemical elements. Many elements occur in different forms, or isotopes, and some of these are naturally unstable and change spontaneously into a different element by the process of radioactive decay. This process provides a natural clock that measures the time that has elapsed since the minerals formed. The clock starts to 'tick' as soon as the mineral crystallises.

By using high precision equipment — a mass spectrometer — the proportion of radioactive decay products can be measured. As these accumulate at a constant rate, we can calculate the time necessary for them to have formed. This is typically many millions of years.

The Stanner-Hanter rocks have been dated using two different sets of isotopes. The decay of rubidium into strontium gave an age of 702 ± 8 million years whereas the uranium-lead system provided a slightly more precise age of 710 ± 1.5 million years.

The oldest rocks in Wales, although 700 million years old, are significantly younger than the oldest rocks found in the British Isles and Europe. These are metamorphic rocks from the Isle of Lewis, Scotland, dated at 3,300 million years old.

The oldest rocks in the world

The oldest dated rocks known in the world are 3,962 million years old, and come from Acasta, north-west Canada. Even these were formed from older, as yet undated, rocks.

Samples of the oldest rocks from Wales, the British Isles and the world can be seen in the Evolution of Wales exhibition at National Museum Cardiff.

A specimen of Paradoxides davidis from Porth-y-rhaw, x 0.75. Amgueddfa Cymru collection

Stage one in the evolution of the north Atlantic area. Triangles indicate areas yielding 'Welsh' trilobites, with dots showing 'North American' forms.

Stage two in the evolution of the north Atlantic area. Triangles indicate areas yielding 'Welsh' trilobites, with dots showing 'North American' forms.

Stage three in the evolution of the north Atlantic area. Triangles indicate areas yielding 'Welsh' trilobites, with dots showing 'North American' forms.

Fossil collecting around the St. David's Peninsula, Pembrokeshire

In 1862 the well-known palaeontologist J W. Salter was collecting fossils in south-west Wales as part of his duties for the British Geological Survey. While examining coastal exposures by boat around the rocky St David's peninsula, Salter one day landed in a small inlet called Porth-y-rhaw, in the mistaken belief that it was Solva Harbour, only a short distance to the east.

His mistake turned out to be extremely lucky, because in the rocks of Porth-y-rhaw, he discovered the remains of one of the largest trilobites ever found (over 50 cm long), and this discovery ensured that the locality became established as a classic and well-known source of fossils.

Life in the sea hundreds of millions of years ago

The dark mudstones exposed there were deposited in an ancient sea some 510 million years ago, during what is now called the Cambrian Period - the name reflecting the fact that rocks of this age were first recognised and named in Wales by the early 19th-century geologists.

Porth-y-rhaw is one of a small number of sites in Wales where Cambrian fossils are reasonably well-preserved and easy to find, and in addition to Salter's giant trilobite it also yields many other kinds of these extinct marine arthropods of more usual dimensions (2-3 cm long).

A National fossil for Wales

The formal scientific name given by Salter to the giant trilobite is Paradoxides davidis, named after his friend David Homfray, an amateur fossil collector from Porth-madog. This trilobite is now one of the best-known from Britain, and is illustrated in numerous publications; choice specimens are among the prize possessions of many of our major museums, including the National Museum of Wales. Indeed, if there were to be a 'national fossil' for Wales, Paradoxides davidis would be the prime contender.

Worldwide Fame

Many specimens of Paradoxides davidis also occur in the Avalon Peninsula of south-east Newfoundland, in rocks of exactly the same age as those exposed in Porth-y-rhaw.

In this context, it is important to understand that in the Cambrian Period, the distribution of continents and oceans was quite different from that of the present day. At that time, Wales, England and south-east Newfoundland all lay on the southern side of an ancient ocean, called Iapetus, and were separated from Scotland and north-west Newfoundland, as shown on the accompanying map.

While the same kinds of trilobites occur in Wales and south-east Newfoundland, quite different ones are common to Scotland and north-west Newfoundland, providing evidence that they once formed parts of different continents.

Snowdon is born

Around 480 million years ago, movements in the Earth's interior caused the ancient Iapetus Ocean to narrow gradually and finally to disappear as two continental masses collided, leading to the formation of a high mountain range of which the Welsh, Scottish, Scandinavian and Appalachian mountains are the present day remnants.

The new Atlantic Ocean

Much later in Earth history, between 200 and 65 million years ago, the two continents began to pull apart again, leading to the formation of a new ocean that was to become the present day Atlantic. However, the new split was not along quite the same line as that along which Iapetus had closed, and left south-east Newfoundland with its 'Welsh' trilobites anchored to the rest of Newfoundland and North America, with Scotland and its 'North American' trilobites attached to the rest of the British Isles.

The occurrence of these same trilobites in areas that today are geographically remote emphasises the need for geologists to study fossils far afield if they are to interpret fully the ancient history of their own local pieces of the Earth's crust.

The oldest objects at Amgueddfa Cymru are in the collections of the Department of Geology. The most familiar are the fossils, ranging in age from approximately 550 million years old down to a little over 10,000 years old.

The Beddgelert meteorite, cut to reveal its internal structure. The dimensions are approximately 9cm x 7cm.

However, there are a group of objects that are considerably older than our most ancient fossils. Unlike fossils, they come not from the Earth, but from outer space.

Many of these extraterrestrial objects fell from space and landed in distant regions of our planet, but one of particular interest was witnessed falling to Earth in north Wales.

Bright lights and shattering slates

In the early hours of 21 September 1949, many people in north Wales and Cheshire saw a brilliant light travelling rapidly across the sky. At 1.45 am a guest at the Prince Llewelyn Hotel, Beddgelert heard a series of dull explosions, followed by three or four seconds' silence, ending with a buzzing sound 'like a light aeroplane' which grew in intensity until a sound of shattering roof slates was heard.

The hotel manager was woken by the barking of his dog, and heard a series of irregularly spaced bangs 'like a naval broadside', but then went back to sleep. The next morning, in an upstairs lounge, his wife found a jagged hole in the ceiling, with plaster and a dark-coloured stone about the size of a cricket ball on the floor. Neither the manager nor his wife knew what this was, nor if it was to do with the sounds heard during the night. However, it was recognised as a meteorite by an old miner in the bar that evening, who had seen some in a museum. A neat, round hole was later found in the slates of the hotel roof.

Meteorites

A meteorite is a natural object that survives its fall to Earth from space. As it passes through the atmosphere the outer layers are heated by friction, causing it to glow brightly and giving rise to the visual phenomena of a shooting star. Meteorites can fall anywhere, at any time, but the chances of being hit by one are (fortunately!) very, very remote indeed.

The Beddgelert meteorite is only the second ever known to come from Wales - the other fell at Pontlyfni, near Caernarfon in 1931. The majority of meteorites probably originate from a cloud of small rocky objects called the Asteroid Belt, which lies between the orbits of the planets Mars and Jupiter in our solar system. Collisions or gravitational forces alter some of their orbits, putting them on a collision course with Earth.

Once found, nearly all meteorites are passed to scientists for examination and analysis, although the Pontlyfni specimen apparently resided under someone's bed for over forty years before being acquired by the Natural History Museum in London!

Both the Beddgelert and Pontlyfni meteorites have been examined by being carefully cut up and distributed between various museums, universities and research institutes. As a result, Amgueddfa Cymru is lucky to have a small piece of the Beddgelert meteorite that fell to Earth in September 1949. This can be seen in the exhibition Evolution of Wales at National Museum Cardiff.

Extraterrestrial rocks older than Earth itself

By dating radioactive isotopes of chemical elements contained in them, the ages of most meteorites, including those from Beddgelert and Pontlyfni, have been determined at approximately 4,560 million years old. This is close to the calculated age of the Earth and the rest of the Solar System. In comparison, the oldest-known rocks formed on the Earth itself are roughly 3,800 million years old (in Wales the oldest rocks are about 700 million years old).

For this reason meteorites are of great scientific interest and importance in studying the earliest history of the Earth and the Solar System, and in giving clues to their primitive condition and how they might have been formed.

One particular class of meteorites (but not Beddgelert), of which there is also an example in the Museum, contains chemicals that were generated with the explosion of huge stars; these include samples of some of the chemical elements that form the 'building blocks' of life, and from which all life - including ourselves - ultimately developed.

Seen a fireball / have you found something which might be a meteorite?

Seen a fireball? Visit:

https://www.ukfall.org.uk/

If you have found something which might be a meteorite, then contact us at: 

https://museum.wales/enquiries/

Amgueddfa Cymru holds fine specimens of prehistoric marine animals, related to the dinosaurs, that swam off the coast of south Wales. Specimens from Dorset illustrate how, once, an ancient sea linked the two areas.

Reconstruction of an ichthyosaur chasing its squid-like prey

Tropical Wales

About 210 million years ago the small part of the Earth's crust that is now Wales lay well to the south of its present latitude, probably close to the northern tropics, where the land formed part of a huge supercontinent called Pangaea. Our climate was hot and humid, with much of Wales comprising barren uplands surrounded by desert-like mudflats. To the south, and spreading far across into Europe, was a series of large lakes.

Wales drowns

As the continents drifted northwards the crust broke up and at various times the seas rose and spread across the land. With these spreading seas came new marine animals that we now see fossilised in the rock record. Some of the most beautiful and spectacular are the marine reptiles known as ichthyosaurs (literally, 'fish lizards'), which were distant cousins of the land-living dinosaurs.

By 200 million years ago, early in the Jurassic Period of geological time, the sea covered southernmost Wales. On the sea-floor, a blanket of fine lime sands and muds was deposited, which have since been compacted into the horizontally bedded mudstones and limestones forming the familiar cliffs in the Lavernock area and extending westwards from Barry to Southerndown.

Abundant fossils

Ichthyosaur remains are not uncommon in these rocks, although they are mostly found as isolated teeth and bones. The fragmentation took place following the death of the animals, when the skeletons were broken up by currents and wave action. Only rarely have more complete specimens been found in south Wales. In contrast, rocks of the same age in Somerset and Dorset have long been known as a rich source of complete or almost complete ichthyosaur skeletons.

The early Jurassic sea extended from the shoreline area of southern Wales across south-west England and beyond to central Europe. In the progressively offshore, deeper-water areas to the south, wave action and coastal currents were weaker, so skeletons were more likely to sink to the sea floor and remain more or less intact. Even so, such skeletons are still found only comparatively rarely today, so we are very lucky to have several almost complete ichthyosaurs in our collections from Lyme Regis in Dorset. Some of the most impressive are on display in the exhibition Evolution of Wales at National Museum Cardiff.

The fact that 200 million years ago the sea was continuous from south Wales across to Dorset means that we can use these beautiful fossils to illustrate part of the history of our area. The Dorset fossils are the same species as those found in the Glamorgan cliffs, and the animals would have been swimming freely between the two regions.

The specimens on display show beautifully the streamlined, dolphin-like shape of the ichthyosaurs. They were adapted superbly for rapid swimming, with propulsion by a large, vertical tail and steering with four flipper-like paddles. Their diet probably consisted mostly of fish and squid.

Williams-Wynn of Wynnstay

Sir Watkin Williams Wynn (1693-1749) - 1740, oil on canvas. 76.2 x 63.2 cm

The Williams-Wynn family of Wynnstay in Denbighshire emerged as one of Wales's wealthiest in the early 18th century, a status they were to retain for over two hundred years.

Several members of the family had an interest in the arts, and Sir Watkin Williams-Wynn (1749-1789), 4th baronet, was to be one of Wales's greatest patrons of the visual arts and music. Much of his collection is now housed at Amgueddfa Cymru.

'The great Sir Watkin'

Sir Watkin Williams-Wynn (1693—1749), 3rd baronet, was the greatest landowner in Wales during the 1730s and 1740s, and a national leader of the Tory party in the House of Commons.

He was the grandson of the politician Sir William Williams (1633/4—1700) who had acquired estates in Denbighshire and Shropshire. However, much of his great wealth was not passed down from his farther, but was generated by to a series of fortunate inheritances from female relations.

In 1719 he inherited the Wynnstay estate in Denbighshire, together with other lands in Caernarfon and Merioneth from his mother's cousin, Sir John Wynn.

In 1715 he had married the younger daughter of Edward Vaughan of Llwydiarth, and by 1725 the death of his wife's parents and older sister had brought him further estates in Montgomery, Denbigh, and Merioneth.

He now owned over 100,000 acres, worth between £15,000 and £20,000 a year, which also gave him great influence over parliamentary elections.

On the death of his wife Ann Vaughan in May 1748, Wynn married his god-daughter Frances Shakerley (1717—1803). Their son, also Sir Watkin Williams-Wynn, and the 4th baronet, was born in April 1749.

Wynn, who was known as 'the great Sir Watkin' and 'the Prince of Wales', was killed in a hunting accident in September 1749.

There are two portraits of 'the great Sir Watkin' in the collections of Amgueddfa Cymru . One of these is the work of Thomas Hudson a fashionable London portraitist who produced polished formal likenesses.

The other is a pastel by William Hoare of Bath, and one of a group of pictures commissioned by Wynn's associate Lord Lichfield.

Wealth and cultural sophistication

Candlestick made in 1734 by the French protestant silversmith Lewis Pantin in the newly fashionable rococo style.

Two pieces of silver also reflect the wealth and cultural sophistication of Wynnstay in his time. These are a pair of large candlesticks, and a massive tripod stand for a tea kettle.

The candlesticks were made in London in 1734 by the French protestant silversmith Lewis Pantin, and are chased and cast with flowers, shells and scrolls —in the newly fashionable rococo style. They formed part of a set of four and are listed in an inventory of silver made on Sir Watkin's death.

A small amount of silver purchased by the family in 1720 survives as an extraordinary rarity as only a handful of these pieces of silver furniture have escaped being melted down for reuse.