The Bonds of Earth by E. V. Thompson
In 1837 when rich deposits of copper ore are discovered, a huge influx of out-of-work miners flock to the area from Cornwall's far west, bringing with them problems alien to the hard-working but easy-going countrymen. Young Goran Trebartha, whose working life is divided between two farms, finds himself caught between the seemingly incompatible cultures, his problems added to when life is further complicated by the arrival of a mine captain and all his female family. Avarice and intrigue, the vicissitudes of farming life and the sheer desperation of hungry miners all add to bewildering changes that will irrevocably alter the course of Goran's life.