28 September 1902
The discovery of diamonds (1867) and gold (1886) transformed South African from an agrarian society at the edge of world trade into a globally integrated industrial economy, which spurred wealth and immigration and intensified the subjugation of the indigenous inhabitants as well as the conflicts between the Dutch and the British. The mineral revolution led to the quick spread of European colonization into the interior. The period saw the making of magnates and migrants, of millionaires and bankrupts, shopkeepers and entrepreneurs. It also saw the emergence of a new working class, one that was deeply divided along both colour and social lines. Racist laws enabled the white-owned mining companies to control workers, keep wages very low and gain immense profits from the diamonds and gold that black miners extracted from the earth. Most African miners became migrant labourers, spending nine to eleven months of the year in the mines while their wives and children remained in the countryside. 10 years after 1886, the Johannesburg town was already the largest in South Africa, outstripping the growth of Cape Town. On 28 September 1902 it was announced that 15 000 applications for gold mining permits were being received weekly in Johannesburg. to read more click The Anglo-Zulu wars  
References

Wallis, F. (2000). Nuusdagboek: feite en fratse oor 1000 jaar. Kaapstad: Human & Rousseau.| Giliomee, H. & Mbenga, B. (2007). New History of South Africa. Tafelberg Publishers, Cape Town.