Barron, H F, Gillespie, M R and Merritt, J W 2011. Geodiversity of the Cairngorms National Park. British Geological Survey Open Report, OR/10/019
A PDF of this report is available from the NORA, the NERC archive
Site no.: B33
Site name: Gairnshiel Bridge
Grid reference:
Locality: Glen Gairn
GCR Status: Proposed
GCR No.: 3100
Type: Natural exposures
Description: Localised, vein-hosted W-Sn-Mo-Bi-Ag mineralisation occurs within zinnwaldite-bearing granite that crops out over ~1 km2 at Gairnshiel, near the centre of the Caledonian Glen Gairn Granite Pluton. The minerals wolframite, cassiterite and scheelite are well exposed in quartz veins and silicified wallrocks. A later mineral assemblage filling cavities in the veins and dissolution zones in the granite comprises either molybdenite or sphalerite, with pyrite, chalcopyrite, and cassiterite, rare stannite and silver-bearing cosalite. The GCR volume' Mineralogy of Scotland' (Smith and Livingstone, in prep) contains a full description of the site.
Justification: The site contains a rich assemblage of metalliferous minerals, including relatively rare ones. Two types of mineralisation occur, neither of which is known to be developed to the same degree in association with Caledonian magmatism elsewhere in the UK.