What happened in 1851 that attracted more settlers to australia

The gold rushes of the 1850s brought a huge influx of settlers, although initially the majority of them went to the richest gold fields at Ballarat and Bendigo, in the Port Phillip District, which in 1851 was separated to become the colony of Victoria.

1851 in Australia was a watershed year. It saw the start of the Australian gold rushes with significant gold discoveries in both New South Wales (near Bathurst) in February and Victoria in July. As a result of the Gold Rushes, the European population of Victoria increased from 97,489 in 1851 to 538,628 in 1861 and the population of NSW increased from 197,265 in 1851 to 350,860 in 1861. Victoria became a self-governing colony.