The superiority which is claimed for Burton ales is attributed to the use of well-water impregnated with sulphate of lime derived from the gypseous deposits of the district.
High, rich in hematite iron ore; valuable limestone deposits are found some 30 m.
Deposits of copper, tin, iron and tungsten have been discovered, and a variety of other mineral products (graphite, mica, spodumene, coal, petroleum, &c.).
The marine facies of the later Tertiaries is confined to the neighbourhood of the coast, and was probably formed after the elevation of the Andes; but inland, freshwater deposits of this period are met with, especially in Patagonia.
The earlier deposits of that sea now rise to the surface in Brittany, the Ardennes, the Montagne Noire and the Cvennes, and in all these regions they arc intensely folded.