Dyeing is a traditional industry of the Zhuang Ethnic Group. The Zhuang in Nanning adore the color of black and deep blue. No matter young or old, people like to wear clothing in all black or a blue shirt and black trousers or a skirt. The dyestuff comes from processing blue indigo. Dyeing is the process of soaking the cloth in diluted indigo repeatedly for at least five or six times until the colour of the cloth turns deep blue. If black colour is wanted, the dyeing process needs to be repeated more than ten times. Then after washing and drying, the dyed cloth is ready to to be made into clothing. Adding a plant called Nanteng grass to the dyestuff causes, some purplish red to appear in the dark blue giving the colours a more splendid and durable appearance.