An Irishman’s Diary: Rock around the clock, a geologist’s view

Far from being a 19th century creation, as unionists might like to think, the Irish Tricolour can be found in the very bedrock of our island, hundreds of millions of years old.

I owe this revelation, and others, to a fascinating book called 648 Billion Sunrises: A Geological Miscellany of Ireland, by Patrick Roycroft.   And it was Roycroft himself who found the flag, embedded in a piece of Leinster granite, from the Dublin mountains.

All right, the colours weren’t immediately apparent. The rock had first to be ground down into a very thin slice, then photographed by a camera attached to a petrological microscope, under special “polarised light”.

But when the geologists did all that that, there, sure enough, were the three vertical rectangles of mica – chlorite for green, muscovite for white, biotite for orange – almost vibrant enough to cause an incident if they were flown over Stormont.

As the author points out, apolitically, you can find many national flags in nature.  Indeed he challenges other "mineral vexillologists" (a speciality he invented) to go looking. But as he says, it's probably only the "simpler flags" that exist in rock form. You're unlikely to find the cedar tree of Lebanon and the Union Jack is a long shot.

On the other hand, Irish geological history also has some encouraging precedents for partitionists. It turns out that long before the current Border, 400 million and more years ago, the land that now comprises Ireland was split in half, along a line between modern-day Drogheda and Limerick.

Until then, the two parts had toured the globe separately: the south-eastern bit spending a lot of time below the equator. Then came the “Caledonian orogeny”, or in the author’s words “a humongous geological Act of Union”.

He also calls it “the most momentous event in Ireland’s history”. Amid all the fun he has with his subject, it is one of Roycroft’s more serious themes that geology is indeed history: a mere extension backwards of the High Kings and Vikings we learned of in school. But he accepts that the subject can be forbidding to the layperson.

So the mission of his “slightly mischievous miscellany” is to give it a human face.

To this end, he suggests that rocks are our “tribal elders”, whose stories help us understand who we are. “But with increasingly immense age, even they can sometimes forget and their speech becomes slurred,” he adds. And that’s where he comes in, teasing out their memories, and interpreting where necessary.

In the process he introduces us to such wonders as the "Blue Waterfall": a 6m cascade of azure rock that you'd expect to hear was in South America somewhere but is actually in an old copper mine in Waterford.

He gives a county-by-county guide of Ireland’s best minerals and fossils, highlighting local specialities such as the fossilised examples of Cooksonia on Tipperary’s Devil’s Bit mountain.

Wicklow gold

Cooksonia is the first plant ever to have grown on land, 424 million years ago and as such the ancestor of every plant and tree alive today, including the giant redwoods.

He also reminds us of the "Wicklow Gold Rush" of 1795.  It saw 4,000 people panning the streams of Avoca and Aughrim before the British authorities moved in and claimed the booty for "Mad" King George.

The biggest find – “the Great Wicklow Nugget” – was 22 ounces of pure gold and allegedly became a snuff-box for said monarch.

In any case, it’s long lost and the best relic we have is a three-ounce nugget in the National Museum.

I heard the voices of the geological elders most clearly in the section of the book where Roycroft discusses the Permian Period, during which “Ireland” was still just north of the equator, with hot dry desert conditions, but on the edge of a shallow sea as well.

One of the results was the gypsum deposits on the borders of what is now Monaghan and Cavan. Hearing about these again I was transported back to the late Quaternary Period, circa 1973, when my siblings and I were occasionally dispatched on mother-relief holidays to our Auntie Mary, in the hills above Kingscourt.

There, every night, we would wait up late for the sound of Uncle Jamesie's car. We wanted to welcome him home, of course. But we also wanted the sweets he was sure to bring back from Tralee, Waterford and other far-flung places, in part return for the treasures he had delivered there, as a lorry driver with Gypsum Industries.