Newgrange VIII

The Newgrange facade and kerbstones consists of stones from various locations, believed to be transported by sea and river.

The Newgrange façade and entrance of today is a creation from the large quantity of small stones unearthed and conserved during excavation given form by a steel-reinforced concrete retention wall. 

The brilliant white quartz cobblestones were collected from the Wicklow Mountains, 31 miles to the south.  Our guide called them “sunstones” for the way they reflect sunlight. In the following photograph is white quartz, the same excavated 1967-1975 from the Newgrange site and incorporated into the facade, I collected from “Miners Way” along R756 (above Glendalough).

You can also see in these photographs dark rounded granodiorite cobbles from the Mourne Mountains, 31 miles to the north.  Dark gabbro cobbles from the Cooley Mountains and banded siltstone from the shore at Carlingford Lough both locations on the Cooley Peninsula where my mother’s family still has farms.

The stones may have been transported to Newgrange by sea and up the River Boyne by fastening them to the underside of boats at low tide. None of the structural slabs were quarried, for they show signs of having been weathered naturally, so they must have been collected and then transported, largely uphill, to the Newgrange site. The granite basins found inside the chambers also came from the Mournes.

Geological analysis indicates that the thousands of pebbles that make up the cairn, which together would have weighed about 200,000 tons, came from the nearby river terraces of the Boyne. There is a large pond in this area that is believed to be the site quarried for the pebbles by the builders of Newgrange.

Most of the 547 slabs that make up the inner passage, chambers, and the outer kerbstones are greywacke. Some or all of them may have been brought from sites either 3 miles away or from the rocky beach at Clogherhead, County Louth, about 12 miles to the northeast.

Click Me for the first post of this series.

Copyright 2023 Michael Stephen Wills All Rights Reserved

Slievenaglogh View, east, V

Looking east

This the fifth and final of a series of landscape photographs taken from this position.

Click photograph for a larger view. To do this from WordPress Reader, you need to first click the title of this post to open a new page.

The peak is named, in the English language, Slievenaglogh. It is so strange as it’s not English, being instead a transliteration of the Irish name “Sliabh na gCloch.” This is “Rock Mountain” translated literally. Slievenaglogh is carried to the townland, a long thin swath of land being the peak and associated ridge-line.

The rocks up there are called “gabbro,” a type of magma slowly cooled under ground. Slievenaglog, Slieve Foy across the valley, and the Morne mountains all formed within volcano magma chamber(s) of the Paleocene, 66 million years ago, a time associated with extensive volcanism and the Cretaceous–Paleogene extinction event that gave rise to the current age.

Our younger cousin has been up there, optimistically we left it for a later trip.

Click for another interesting post and story from County Louth.

Here is a slide show of this landscape series.

A link with interesting reading on County Lo uth geology.

Copyright 2022 All Rights Reserved Michael Stephen Wills