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From ‘Scotch on the Rocks’ by Stephen and Julia Cribb, published by the British Geological Survey, adapted by Mark.

Bruichladdich milks the rocks from South America

Bruichladdich is located on, and uses water peculating through the oldest rocks of any distillery in Scotland – 1800 million year old Gneiss.

Whether looking at the map or standing on the shores of Loch Indaal, it is obvious that both physically and geologically, the far west of Islay, The Rhinns, is different from the rest of Islay. Indeed in earlier times, when the sea levels were higher, it would have been a separate island.

It is separated geologically from the rest of Islay by a major break in the rocks, along which a substantial earth movement occurred. This feature is known as the Gruinart Fault, which passes from Loch Indaal through the narrow neck of land in to Loch Gruinart.

Almost all of the rocks to the east of the fault, including Jura, were formed 800-600 million years ago (in the Dalradian part of the Precambrian period), folded into an anticline (the Caledonian Orogeny) causing the rocks to recrystalise (metamorphise).

These Dalradian rocks are very old - but the Rhinns Gneisses, to the west of the fault - are even older, 1800 million years older, making them the oldest in Scotland bar the rocks of Lewis in the Outer Hebrides.

These Rocks  are  3 times older than  the rest of Islay,  4 times the age of the Granite of the Speysiders such as Glenfiddich, Glenfarclas, Macallan etc… 5 times older than the sandstones of Glenmorangie, and 30 times older than the Volcanic Basalt of Talisker. As Andrew Jefford says in his excellent book Peat, Smoke and Spirit,to put it in to perspective, the Bruichladdich Gneiss is 225,000 times older than the English Channel. Imagine the history of the earth as a single day, the 24 hour clock: The gneiss of Bruichladdich was formed at about 14.00, the dinosaurs appeared at 22.48, and were gone by 23.40, and we humans arrive at 23.59 and 52 seconds! These are old rocks - there are not even any fossils – there was nothing alive when these rocks were formed deep inside the earth’s crust.

The Rhinns rocks fall into two categories:

Spectacular, hard, dark green and pink banded, high grade metamorphic rocks called Amphibolite Gneisses, formed deep in the crust of the earth, make up the southern part of the peninsula, including the hill of Beinn Tart a'Mhill behind Bruichladdich and are well exposed on the west coast and on the beach in front of the Distillery.

Grey-brown, hard, sedimentary sandstones occupy the lower, boggier, ground in the north of the area, as well as the island of Colonsay further to the north.

Water for the distillery, having percolated through the oldest rocks in the distilling industry, drains from the low boggy hills near the boundary between the sandstones and the gneisses, and is collected in a shallow loch in the hills behind the distillery from where it is piped to the Mash House.

Bruichladdich are the  only people to bottle their whisky on the island, the whisky benefiting from the crystal clear water used to dilute from cask strength to the preferred 46%.  It comes from a secret spring in  Gleann Mohr that slowly wells up from deep down in these ancient rocks, and is preferable to a municipal town supply in a mainland industrial estate.

And South America?

1000 million years ago, the planet consisted of 3 great continents:

Laurentia (North America & Greenland & North Scotland) Gondwanaland (South America & Africa) Baltica (Europe) Scotland formed part of the continent of Laurentia and England formed part of the continents of Avalonia and Baltica.

It is believed that when the continent of Laurentia split from Gondwanaland  around 600 million years ago and moved apart (Plate tectonics), the Rhinns bit of Islay split along the Gruinart fault, and went off with Gondwanaland (South America). Between these continents lay the Iapetus ocean.  The continents  then moved back towards each other, closing the ocean. During this time, the ocean floor was subducted  - sunk underneath the overriding continental crust of  Laurentia.

In the Caledonian Orogeny, the mountain-building event that occurred 430 million years ago, the final closure of the Iapetus Ocean caused the two continents to collide again, uniting England and Scotland and reuniting the Rhinns with the rest of Islay; subsequently the land masses moved apart, but this time splitting along the present day west coast of Islay (from Portnahaven to Ardnave Point) to be separated by the Atlantic Ocean. And what became of the land mass that moved away leaving the Rhinns? It became the Arequipa Coast of Peru.

The geological feature from which the  Gaelic name Bruichladdich is derived (“brae on the shore” or “shore bank”) was created only 10,000 years ago after the last ice age. The melting of the ice caps the land to rise in relation to the sea level (isostatic readjustment) thus creating a new coast line  and leaving the previous one high and dry – a raised beach, or ‘shore-bank’ that is easily recognised on the right-hand side when coming from Bridgend to Portnahaven, as well as behind the car park at the distillery.

The Rhinns’ gneisses have travelled for a 1000 million years to provide an exotic whisky in terms of taste and geological romance; and their journey will continue for a thousand million more.

So Bruichladdich; A raised beach on the oldest rocks in Scotland’s distilling history… …and to think we could be living in Peru…