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Here  we have some thin sections and some hand specimens, and maps showing were they are from . . .

Sadly, some files were corrupt, so we don't have all the details!

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LOCH BORRALAN INTRUSION

I. Parsons

OS Grid Reference: NC235110– 277081– 297085– 306107– 298140– 260150– 235150

Introduction

The Loch Borralan intrusion, in the SW corner of the Assynt region (Figure 7.2) is of international importance for petrological reasons, and of great regional significance for structural reasons. It is the only plutonic complex composed largely of silica-undersaturated (i.e. feldspathoid-bearing) igneous rocks in the British Isles, and many of its members are exceptionally alkaline. It provides Britain's only example of truly ultra-potassic magmatism.

The most potassic members, with as much as 15 wt% K2O, are among the most K2O-rich rocks encountered on Earth. The site includes the only British example of carbonatite.

Further details here.

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No further details available

No further details available