Rock – industry’s raw material
Man has exploited the mineral wealth of East Lothian and the Borders for at least 800 years.
Coal occurs in numerous seams in the coalfield basin from the sea at Musselburgh and Prestonpans inland to Tranent, Macmerry, Ormiston and Pathhead. Because of folding and faulting the seams come to the surface in numerous places.
Limestone, though bedded like coal, is not normally deep-mined. It was usually worked in small quarries and ‘burned’ with coal in limekilns, such as Catcraig near Dunbar, to produce agricultural lime used to ‘sweeten’ or reduce the acidity of the soil. Nowadays only the extensive quarry at Oxwellmains works limestone, where it is crushed, mixed with mudstone, and roasted in rotary kilns to produce cement for the building industry. Restoration has returned the land to agricultural use, but much of the original character of the land is lost as a result.
Volcanic and intrusive rocks have been quarried at many sites as Whinstone for concrete aggregate and roadstone. Intrusions are harder and less weathered than lavas, so are more widely used.
In East Lothian almost every hill or ‘law’ has been quarried in the past. Even North Berwick Law had its quarry, later used as a refuse tip and almost fully restored. At Traprain Law the quarry was closed following public outcry before the characteristic outline was irreparably changed.
Many of the upstanding hills in the Borders, too, have been used, such as Dunion Hill at Jedburgh, and Redpath Hill not far from Scott's View. Fortunately, though, these can be worked in such a way not to affect the skyline. Greywacke can be as hard as the volcanic rocks, so has frequently been quarried as ‘whinstone’ where there is no good igneous source.