Geology and man, Northern Highlands of Scotland
From: Johnstone, G S and Mykura, W. 1989. British regional geology: the Northern Highlands of Scotland (4th edition). (Nottingham: British Geological Survey.)
Minerals with an economic association are widespread in the Northern Highlands, but in only a few places are they found in sufficient concentration to warrant exploitation.
Most of the main prospects have been known since the 18th century, mainly as a result of specific prospecting surveys carried out on behalf of the large landowners and, following the 1745 rising, the Commissioners for Forfeited Estates. It is evident that the old prospectors were well versed in the detection of vein ores and other concentrations of metallic minerals. Modern prospecting has been for bulk minerals, non-metallic minerals and low-grade ore deposits which, while not readily visible in outcrop, are still capable of abstraction by bulk handling and beneficiation.
A number of surveys were carried out on behalf of the Ministry of Supply during the 1939–45 war, and the Scottish Council (Development and Industry). Investigations that ranged more widely were subsequently undertaken by the Geological Survey as part of their Regional Geochemical Survey and their Mineral Reconnaissance Programme. The survey was sponsored by the Department of Industry, the programme in part by the Atomic Energy Authority. Additional investigations were undertaken by Robertson Research Ltd sponsored by the Highlands and Islands Development Board. The later investigations made use of all modern geophysical and geochemical techniques. While several prospects have been located, none in the Northern Highlands have so far warranted major economic exploitation. Reports are listed in the bibliography.
Several Special Reports on the Mineral Reserves of Great Britain cover specific aspects of the economic mineral potential of the Northern Highlands; they are out of print. However, a comprehensive survey of the actual and potential economic minerals of the Northern Highlands is given in IGS Report 69/5 A summary of the mineral resources of the Crofter Counties of Scotland. More detailed summaries of the availability of sand and gravel aggregate are given in IGS Reports 77/8 and 78/8, and in the series of mineral dossiers published by the Mineral Resources Consultative Committee.