Howardites
Meteorites of Britain and Ireland · Wales

The Pontlyfni meteorite

The only winonaite ever seen to fall anywhere in the world, recovered on the Welsh coast.

Key facts

Fell
14 April 1931
Where
Pontllyfni, near Clynnog, Gwynedd
Type
Winonaite (primitive achondrite)
Mass
157 g recovered
Where it is kept
Natural History Museum, London, and a private collection
Nation today
Wales

On 14 April 1931, after loud reports were heard on the north coast of the Llŷn peninsula, a farmer at Pontllyfni saw a stone fall near his farmhouse. It had made a hole about 20 centimetres deep. Only 157 grams were recovered. The main mass probably fell into the sea, which lies only a few hundred metres away.

For decades the stone was little studied. When it was examined properly, it turned out to be extremely rare: a winonaite, a kind of primitive achondrite. Winonaites come from a body that was heated almost to the point of melting. Their minerals recrystallised and some metal and sulphide melted and moved, but the rock never fully melted, and faint traces of chondrules may survive. Their oxygen isotopes match those of the silicate rock found inside IAB iron meteorites, so winonaites and IAB irons probably come from the same parent body.

Only a few dozen winonaites are known, and every other one is a find. Pontlyfni is the only winonaite ever seen to fall, which makes this small Welsh stone one of the most important meteorites in Britain.

Did you know?

Did you know?

Pontlyfni is the only witnessed winonaite fall in the world.

Did you know?

The village name is usually spelled Pontllyfni; the meteorite keeps the older spelling Pontlyfni.

Find out more

Nearest other British and Irish meteorites

Related pages

Meteorite types: Winonaites