SABHAIL AMPHIBOLITE
The unit is well exposed forming a small subsidiary ridge Cnoc an t-Sabhail (NGR 80567664) on the Southwest flank of Meall na h-Iolaire. The unit is not laterally continuous with it being faulted not to the Southeast by a small fault which forms a valley running up the hillside, and disappearing to the north west (either due to faulting or modern erosion).
The boundary with the Torr schist to the Northeast is not exposed but the two units had a nearest approach of 0.5 metres, and it is believed that the boundary is steeply inclined, possibly vertical. The boundary to the Southwest was not exposed but was delineated by the Gairloch schist.
Exposed surfaces of the Sabhail amphibolite are coloured black with distinctive white feldspar rodding being readily recognised. Overall the rock presents an homogenous appearance with a very weak (none measurable) foliation developed. The fresh surfaces show a green-black colour with a fine grain size (individual minerals could not be distinguished in hand specimen). However, the mineralogy is believed to include amphibole and biotite, which form the bulk mineralogy of the rock with minor amounts of garnet, feldspar and white mica. The feldspar rods are 3-4 millimetres in diameter and represent the "L" fabric of the rock.
No structures where observed in the Sabhail amphibolite.
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