What is Gneiss ?

The rocks of the Outer Hebrides are the very oldest rocks to naturally surface in the United Kingdom with some in Barra well over 3 billion years old.

Collectively most of the rock is classified as ‘Lewisian Gneiss’ (pronounced ‘nice’) which turns out not to be simple rock form, rather it is a product of varying ingredients, some igneous (volcanic) in origin and some the amalgamated products of erosion which have gathered to form sedimentary thicknesses, before all these ingredients, regardless of origin, have been baked, squashed and melted, perhaps many times, cracked up in movement, injected with fresh material from deep within the earth and cooked, squished and melted again over almost unfathomable eons, as millions of years of heat and pressure separated and glued their minerals and cooked or cooled their crystals in bands of differing size and composition!

TIME & SPACE

The sheer time involved in producing these ancient ‘metamorphic’ rocks is vastly outside of our human time frame. Each piece pre-dates life going right back to the geological period we call the ‘Archaean’, which it’s self came only just after the first geological period we call the ‘Hedaean’, which was when hard crusts initially cooled on the surface of the Earth from the primordial molten fire ball we’ve now somehow come to inhabit, all left over from a spinning disk of ancient sun dust.

Each fragment of rock, in addition to traveling through deep geological time, has traveled through space over vast distances.

Not only on the spinning arm of our spiral galaxy hurtling through the void over a large chunk of all universal existence, but in our very spherical sense, these rocks have navigated our globe, with most of the actual Gneiss material, having originally formed over the South Pole near present day Antarctica, before gradually wandering north, pushed on giant plates, creaking, cracking and grinding about the globe with roughly the speed of growing fingernails, until we somehow chose to borrow it briefly for use and/or ornament from the rolling breakers and thundering waterfalls of the present day North Atlantic.

The minerals within Gneiss have been separated into light and dark mineral layers and all folded and squashed together in deep time.

The light layers include Quartz and Feldspar with the darker layers containing Iron and Magnesium among countless other minerals.

Pink Granites have been injected in swarms of cracks and various other classifications of volcanic rocks exist in bands and blobs sometimes as large as mountains.

The spectrum of rocks found in the Western Isles is coloured vividly by the complex geology of South Harris, where bands of rarer rock, sometimes sedimentary in origin, transect the island from east to west to shape the brutally majestic, glacially carved landscape. In these rich bands can be found the very rarest of marbles, garnets beyond number and sparkles from graphite and pyrite in schists. We select our choice material most sparingly and cut with real reverence into these stones which hold such precious history.

So, to attempt to answer the question: What is Gneiss?

Gneiss is a complicated material, not simplistic in origin, with a history longer than life and a future of travel and adventure.

We think,

under scrutiny;

It’s well named.