Complex sentence: During its boom days the town served the needs of thousands of diggers and prospecters working for the Schiller, Montrose and Dunmore mining companies, whose arrival was sparked by Sir Thomas Cullinan discovery of a rich kimberlite diamond pipe in the town named after him.
Split into simpler sentences: During its boom days the town served the needs of thousands of diggers and prospecters working for the Schiller, Montrose and Dunmore mining companies. This mini diamond rush was sparked by Sir Thomas Cullinan's discovery of a kimberlite diamond pipe in the town since named after him.